Smithells Metals Reference Book Part 4 pot

Aluminium a Concentrated Keller’s and its alloys Reagent Nitric acid 1.40 lOOml Hydrochloric acid 1.19 50ml Hydrofluoric acid 40yJ lpml b Nitric acid 1.40 30ml Hydrochloric acid 1.19 30

Physical properties of molten salts 9-33 Table 9.5 ELECrRICAL CONDUcnVITY OF MOLTEN BINARY SALT SYSTEMS AND OTHER MIXED IONIC MELTS-

P GOO K600

K700 Ksoo

P

lES50 K650

K 7 S 0

P

K 5 5 0 K60O K?O0

P

K s 0 0 K600 K700

P

KSOO K500

K 7 0 0

P

K 5 0 0 KSOO

40

-

-

1.55 1.81

0

6.0 6.4 43.9

-

(2.25) (24) 2.7

0 1.44 1.88

228

0 1.35 1.70 1.95

0

-

-

1.32 1.52 39.4

-

-

0.26 36.9

-

-

0.46 15.1

-

- 0.31 9.0

-

-

0.47 0.60 1.05 1.56 0.55 1.00 8.3 2.40 2.55

14.2 0.35 0.56 0.79 1.05

50

1.10

1.24 1.48 1.73 59.1 4.1 4.5 67.6 1.95 2.15 2.45

20

1.68 1.94 2.35

10

1.30 1.66 1.86 19.7

-

-

- 1.21 1.45 44.6 0.17 0.25

50.0

-

-

- 0.44

28.6 0.22

0.34

18.1 0.29 0.31

0.54

1.8

202 1.03 1.92 19.5 1.69 1.79

-

-

332 0.18 1.03 1.30

60

1.11

127 1.48 1.66 81.2 2.8 3.2 3.5 82.5 1.9 2.1

2 4

40 1.97 2.36

25 1.12 1.56 1.76 35.5

021 0.32 27.5 0.14 0.25 0.38 0.50 2.8 2.59 1.43 2.74 52.1

1.40 1.50

59.9

-

-

1.32 1.57

70 1.19 1.36

1.60

1.78 92.9 2.3 2.6 3.0 92.6 1.85 2.0 2.3

0.30

0.66 1.06 1.26 64.5 0.07 0.15 0.23 70.0 0.12 0.23 0.35 51.7

0.10

0.20 0.31 37.1

0.1 1

0.22 0.34

0.46

3.4 3.26 2.07 4.75 59.2 1.21 1.30

100

21

2 3

100 1.8 1.9 2.2

80 1.94 2.26

60

1.41 1.66 1.86 75.3 0.31

0.64 0.99

0.10

0.19 0.29 47.0 0.08 0.17 0.28 0.40 3.9 3.81 2.87 8.88

-

90

1.52 1.71 1.97 2.09

100

1.88 2.20

80

1.81 1.99 89.8 0.57 0.89

0.04

0.12 0.23 70.6 0.08 0.16 0.26 57.1

-

- 0.23 0.34 4.7 4.45 3.7 15.5

100 1.96

218 2.25

-

100 1.97 2.10

100 0.41 0.95

-

-

-

0.26 5.3 5.35 6.1

c 60

P Kg00

0

1.530 1.490 0.0 0.42 0.0 0.50 55.9 0.5 0.8 32.6

48

48 15.0 1.4 2.0 3.6

0.0

0.47 0.0 0.41 61.19 0.4 0.55

0

-

-

- 0.028 0

71.42 0.7 0.95

0 0.4 1

0.476 0.536

63.8 0.09

0.13

52.2 1.61 1.70 62.3 0.7 42.0 2.00 2.07

218

232

30 3.2 5.0

-

25 9.30 9.40 9.50 0.9

0.46

1 .o

0.55 63.3 0.9 1.6 35.7

50

47 19.4 3.8 5.8 10.6 0.4 0.58 0.3 0.43 78.63 0.5 0.7

20

0.029 5

0.028 1 0.025 2 81.82 0.9 1.15

10

0.344

0.397 0.450

79.9

0.20

0.26 71.0 1.50 1.58 72.0 0.8 47.6

-

35 8.20 8.30 8.30

2 7 0.54 3.0 0.67 68.6 1.4

2 3 56.5

40

34 30.5 6.8 11.6

- 1.3 0.87 0.6 0.45 84.66 0.6(2) 0.8(2)

40

0.016 0

0.0160 0.0160 83.54 0.7 1.1

20 0.274 0.320 0.368

87.0 1.45 1.55 81.5 0.9 57.5 2.23

232 2.44 2.59

50

5.5 10.0

-

50 4.60 5.20

-

4.9 0.65 3.8 0.69 12.4 2.1 4.0 62.1

38

33

2.3 1.27

1 .o

0.49 89.57 0.6 0.75

50 0.009 4

0.009 7 0.0104 86.12 0.8 1.15

40 0.184 0.226 0.269

90.8 1.2 76.0 2.71 2.82 2.94 3.08

65 3.30 4.60

-

7.8 0.76

75.4

3 2 5.0 91.9

145

155

2.7 1.46

93.64 0.45 0.6

60

0.005 3 0.005 6

0.006 3

9221 0.55 0.75

50

0.150

0.186

85.9 2.93 3.06 3.20 3.34

75

220 3.80

-

12.0 0.90

78.7 4.2 7.8 97.2

93.84 0.78

1 .o

60

0.126 0.156

-

100 3.32 3.43 3.54 3.66

100 0.50 1.30 1.70 16.7 0.98

84.9 9.0

-

100

-

- O.Oo0 8

9531 0.4 0.6

75 0.100

-

Physical properties of molten salts 9-35 Table 9.5 ELECTRlCAL CONDUCTIVITY OF MOLTEN BINARY SALT SYSTEMS AND OTHER MIXED IONIC MELTS- continued

P

K60D K700

KSOO

P

IC400 K6O0

0 0.476 0.536 0.596 0.0 0.53

1 5.6 6.8

1 3.8 1.35 4.5 0.5 4.5 0.5 3.7

-

-

33.7 2.97 3.05 19.7 1.64 1.70 1.80 2.2 0.489, 3.239, 0.835, 537-70 I

35.8 0.10 0.12 0.16 2.8 1.31 1.52 1.66

80.4 0.48 0.56 0.64 75.82 0.4 0.5

20 0.302 0.348 0.395 0.7 0.56

2 11.7 16.3

2 6.2 2.72 6.7

1 .o

8.5 1.2 7.9

40

-

-

8.0 17.2 0.79 1.34

40.0 0.15 0.21 7.8 1.38 1.56 1.72

-

86.5 0.64 0.69 0.75 82.47 0.5 0.73

40

0.174 0.210 0.248 3.2 0.69

3 22.4 29.5

4 14.1 4.10 12.0 1.5 13.5 2.6 19.7

50

3.0

10.0

37.0 0.78 1.29

-

-

-

85.9 2.20 2.29 59.5 1.64 1.70 1.80 9.7 2.008, 3.845, 7.546, 650-762

K,=a+bt

91.6 0.64 0.69 0.75 87.98 0.6 0.77

50

0.154 0.182 0.214 6.3

500

60

5.3 11.5 54.1 1.30

23904 8.864, 4.9049 619-717

etz

44.4 50.2

0.14 0.16 0.19 0.23 13.3 26.8 1.41 1.48 1.61 1.70 1.76 1.88

96.1 0.43 0.45

- 92.62 0.55 0.7

60 0.136 0.161 0.187 10.6 1.05

6 104.7 129.0

8 64.6

-

30.3 0.475, 3.284, 0.84S0 626-791

60.0 0.21 0.25 0.33 41.2 1.56 1.80 1.97

100

0.03 0.03

- 96.58 100 0.37 0.03 0.4 0.03

0.156 0.0305 0.171 0.0280

8 229.2 263.0

10 117.5

128 12.6 86.9 io0

64.7 73.0 0.24 0.34 0.29 0.41 0.39 0.55 64.4

1.66 1.96

214

9-36

Table 9.5

continued

Physical properties of molten salts

ELECTRICAL CONDUCTIVRY OF MOLTEN BINARY SALT SYSTEMS AND OTHER MIXED IONIC MELTS-

K600 K700

IC350

P

K800

P KSOO

Ksso Ksoo K6S0

10 1.10 1.33 1.50 22.0

264 2.76 18.7 3.23 3.50

0 2.41 2.68 2.8 1.414 1.645 1.868

326

1 .o

0 0.09 0.16 0.26 0.37 19.0 0.09 0.14

0

0.56

0.72 0.95 33.20 2.6 3.4 4.2

-

28.2 3.51 4.10 4.56

20 1.17 1.37 1.54 32.0 2.40

253

321

298 3.24 8.0 1.88 2.20 2.51 4.5 1.176 1.401 1.609 1.807

0.09

0.12 0.16 24.4 0.52 0.66 0.88 49.85 2.9 3.6 4.3

426

2 3 1

287 3.42 3.82

30 0.97 1.21 1.39 1.56 51.4 2.29 2.39 40.6

252

285 3.11 19.8 1.68 2.04 2.37 6.1 1.142 1.345 1.558 1.723 1.913

-

39.8 1.70 1.77 1.89 8.7 0.995 1.215 53.0 1.3 17.8 0.64 0.77 0.90 1.02 29.3 0.13 0.17 0.24

421 0.42 0.64 0.74 66.54

3 2 3.7 (4.4)

55.8 1.87

240

288 3.24

50 0.98 1.24 1.44 1.62 74.0 2.21

232 54.8

235

264 2.88 33.0 1.54 1.86 2.16 14.8 1.034 1.205 1.364 1.515 1.684

-

63.9 1.88 1.98

209 14.1 0.865

65.9 1.5 26.3 0.70 0.82 0.95 1.06 33.7 0.16 0.21 0.27 55.5 0.35 0.48 0.67

100 4.1 4.5

-

72.2 1.90 2.35 2.72

60

0.97 1.27 1.48 1.67

20.3 0.688 0.871 81.4 1.8 35.9 0.76 0.89 1.01 1.14 39.8 0.21 0.25 0.32 74.4 0.22 0.34 0.52

87.6

-

-

204 2.36

70 0.98 1.34 1.56 1.75

829

234

256 73.6 1.87

217 37.9 1.038 1.174 1.306 1.467 1.624

-

-

-

27.8 0.472 0.645

526 0.78 0.92 1.05 1.19 50.0 0.30 0.35 0.44 87.1 0.17 0.26 0.41

-

(1.110) 1.230 1.350 1.519 1.670

31.9 0.702

-

58.7 0.79 0.95 1.09 1.24 56.8 0.36 0.41 0.51

100 0.20 0.35

-

Physical properties of molten salts 9-37 T&e 9.5 ELECTRICAL CONDUCTIVITY OF MOLTEN BINARY SALT SYSlZMS AND OTHER MIXED IONIC MELTS-

K700 K800

- 3.660 6 0.942 8

- 5.010 1 760-869

-

55.0

224

258 50.9 0.08 0.10 27.5 0.336 5 614-804

Kf =a+ bt +et2

1.262 1.176 1.108 1.472 1.380 1.308

0.51 0.52 0.63 0.65 31.6 41.8 0.04 0.06 0.06 0.08 0.07 0.12 78.0 83.4 0.71 0.80 0.85 0.94 81.9 87.5 1.18 1.22 1.29 1.33 37.4 50.5 2.8156 2.8809 0.5601 0.6150 2.0875 2.501 1 891-1010 759-912

40 0.706 1.024 1.351 31.4 0.42 0.55 0.68 52.0 0.05 0.08 0.12 89.0 0.87 1.00 92.3 1.28 1.37 58.3 2.311 1 0.549 2 2.4324 754-770

45.1 1.244 1.434 1.625 1.052

-

M 0.652 0.966

1284 40.7 0.57 0.70

-

94.5 1.04 94.5 1.30 1.39 67.4 2.3562 0.565 0 2.392 3 674-819 0

-

-27280 -5.3073

55.3 0.998 1.185 1.366 1.548

-

60

0.625 0.931 1.234 56.0 0.59 0.73

-

100.0 0.92 1.05 96.6 1.31 1.40 76.6 5.493 6 1.250 1 5.882 2 773-955

4.1 7.35 4.6 5.02 4.4 20.9

100 1.32 1.52 67.3 0.21 0.24 0.28 79.4 91.0 6.0644 4.2506 8.173 1 5.507 5

-

-1.2999 -0.8537 882-934

74.2 1.040

1204 1.365 1.525

-

80 0.572 0.874 1.178 73.3 0.63 0.77

-

98.3 1.39 1.48 85.0 7.543 6 1.640 2

100 0.818 1.107 86.0 0.64 0.79

-

-

100 1.40 1.49

922 38.80 7.964 6 7.5248 39.636 842-1 016 885-1 029

15.8 25.9 6.2

7.21

9-38 Physical properties of molten salts

t range

a

P K200

KZSO

K300

P

1026 10%

io-%

P

Ksoo K9OO

10.470 8 2.498 1 13.536 778-917

10.5

-

-

0.43 54.6 6.015 2 1.333 6 5.594 8 805-952

23.2 2.80 2.96 3.12

5 2.5

40 2.32 4.8

-

21.4 1.06 1.45

-

0.25 4.0 4.8 0.25 4.3 4.4 0.4 3.7 4.5 5.0

0 5.4 5.1 5.9

16.7 0.20 0.33 0.47 59.7 2.149 1 0.455 8 0.392 3 769-924

39.1 2.31

249 2.67

26.4 1.07 1.41

-

0.5 6.3 7.7 0.5 4.9 5.0 0.6 3.5 6.5

20 4.9 5.1 5.4

50

3.0 5.0

120

-

-

51.5 60.5 4.031 1 4.6127 1.0289 1.1832 4.489 7 5.21 1 7 768-917 799-945

K,= -a+bt-ctz 23.8 31.9

0.36 0.41 0.51 0.56 69.0 77.5 7.4648 0.6063 1.7642 0.1086 7.6694 -1.9898 757-938 735-890

K , = -a+bt-ct2 57.2 69.0 1.97 1.78 2.16 1.98 2.35 218

1.85 2.25 3.1 3.4 a-b/(t+273) at 1600-

51.2 62.2 0.86 0.80 1.17 1.11

- -

0.75 1.0 1.4 8.2 9.7 11.5 0.75 1.0 5.3 5.7 5.5 5.9

1.5 3.0 5.0 6.0 8.0 10.0 14.0 15.0

- -

71.3 2.795 8 0.753 9 2.887 845-956

52.3 0.53 0.72 85.2 5.259 7 1.277 3 4.823 7

-

716-897

81.5 1.63 1.82 2.01

65 2.94 4.6

1 800 71.2 0.75 1.08

-

1.5

14.7

1.5 6.4 6.7 1.6

80 3.5 6.5 10.5 15.5

85.2 21.3359 5.368 6 30.734 764-872

65.2

0.61

0.82

923 5.723 7 1.404 8 5.7978 734-907

-

90.3 1.39 1.57 1.75

70

221 2.5

83.1 0.63 0.75

-

2.0 17.5

90 4.0 7.0

10.5 15.0

91.0 13.2305 3.225 9 16.322 809-908

Physical properties of molten salts 9-39 Table 9 3 ELECTRICAL CONDUCTIVITY OF MOLTEN BINARY SALT SYSTEMS AND OTHER MIXED IONIC MELTS-

P KTOO

P

Ksoo

P

KSOO K82S K35O

P

K 3 0 0 K350

K400 K450

Ksso

17.7 1.18 2.00

0 2.4 2.8 43.8 1.32 1.83

0 1.445 1.91 27.5 1.75 11.5 0.46

0

1.16 1.36 1.55 28.3 0.32 0.74 45.9 4.450 9 0.962 5 4.036 4

-

-

780-923

0.4 0.53 1.7 1.20 0.3 0.476

0 1.43 1.69

-

25.0 1.14 1.96 52.45 2.2 3.1 3.1 60.4 2.20 2.60

255 1.51 1.95 36.2 1.75 34.9 1.45

1.5 0.61

2 4 1.24 0.9 0.585 23.7 1.34 1.56

I

30.4 1.03 1.83 68.81 2.3 3.0 3.4 60.7 2.19 2.59 9.01 1.58 2.005 47.0 1.9 59.7 1.74 1.83 1.97 33.3 loo0 4.961 44.8 0.72 1.32 44.8 1.11 1.34 1.58 1.79 44.6 0.38 0.56 1.16 55.7 4.563 4 1.032 6 4.455 5

-

39.8 0.95 1.75

71.8

298 20.05 1.645 2.07 60.3

23 75.1 2.41 2.83 3.01

-

-

-

1050 5.407 52.8 0.63 1.23 65.4 1.19 1.44 1.69 1.92 51.7 0.47 0.80 1.55 65.1 7.2754 1.720 1 8.5600 767-905 741-881 K,= - a + b t - c r z

0.79 0.94 3.8 7.3 1.32 1.54

0.759 1.033 45.3 66.6 1.02 0.97 1.25 1.17 1.45 1.36

48.4 0.83 1.63

73.6

294

-

77.4 2.7 88.1 2.88 3.08 3.34

-

-

1100 5.642

82.1 1.25 1.51 1.78 2.02 60.0 0.56 0.90 1.76 74.2 3.1368 0.7399 2.4220 689-850

11.4 1.01 11.0 1.67 8.1 1.102 83.8 0.91 1.10 1.26

523 0.79 1.59

100 3.34 3.60

88.7 2.68 3.36

-

-

100 1.34 1.62 1.89 2.10 65.5 71.6 0.70 0.86 0.94 1.15 2.10 2.54 83.0 91.6 6.0743 2.7481 1.5506 0.671 8 7.194 3 2.495 8 653-803 701-869

13.9 15.4 0.96 0.92 14.6 18.6 1.77 1.84 11.1 11.5 0.980 0.930

100 0.84 1.03 1.19

-2.9

71.2 78.8 -2.0 -1.2 -1.2 -0.6 1.1 2 5 0.80 1.10

1.3 2.6 1.28 248 54.0 64.6 0.95 1.0 12.8 17.9 0.48 2.34 (610) 3.77 (790) 3.94 (790)

84.8 -0.7 -0.2 4.1 1.47 4.2 4.24 75.8

1.2

22.4 1.30 3.94

89.7 -0.3 0.0 5.8 1.90 6.3 8.25 87.6 1.4 29.7 3.85 1.18 (605)

93.7 97.1 0.0 0.2

0.2 0.6 8.6 8.7 2.38 2.67

14.8 21.0

39.7 52.0 1.46 0.050 3.68 (795) 293 (805)

~~~

*See also Na,AlF6-NaF

** See ulso ‘Physical Propties Data Compilations Relevant to Energy Storage I1 Mohcn Salts: Data on Single and Multi- Component Salt Systems’, I Janz et al., NSRDS-NBS 61, Part 11

t Melts may contain up to l%MgO

t See ulso AIF,-Na,AIF,

REFERENCES TO TABLE 9.5

1 H M Goodwin and R D Mailey, Phys Reo., 1908, 26, 28

2 V A Izbekov and V A Plotnikov, J Russ Phys-Chem Soc., 1911, 43, 18

3 C Sandonnini, Gazz Chim I d , 1920, SO, 289

4 K Arndt and W Kalass, Z Elektrochem, 1924, 30, 12

5 V A Plotnikov and P T Kalita, J Russ Phys.-Chem Soc, 1930, 62, 2195

6 E Ryschkewitsch, Z Elektrochem., 1933,39, 531

7 S V Karpachev, A G Stromberg and 0 Poltoratzkaya, 3 phys Chem (USSR), 1934,5, 793

8 V P Barzakovskii, Proc 1st All-Union Cod on Non-Aqueous Solutions, 1935, 153

9 K P Batashev, Metallurg (USSR), 1935, 10, 100

10 S V Karpachev, A G Strombexg and V N Podchainova, J Got C h e n (USSR), 1935, 5, 1517

11 M de Kay Thompson and A L Kaye, Trans Electrochem Soc., 1935,67, 169

12 K P Batashev, Legkie Metal., 1936, 10, 48, quoted by V P Mashovets, The Electrometallurgy of

13 Ya P Mezhennii Mkm Inst Chem, Acad Sci Ukruin S.S.R., 1938, 4 413

14 Y Yamaguti and S Sisido, J chern SOC Japan, 1938, 59, 1311

15 A I Kryagova, J Gen Chem (USSR), 1939, 9,2061

16 A A Sherbakov and B F Markov, J phys Chem (USSR), 1939, 13, 621

17 V P Barzakovskii BUN Acad Sci U.R.S.S., Class Sci chim., 1940, 825

18 V P Barzakovskii, J appl Chem (USSR), 1940, 13, 1117

19 A G Bergman and I M Chagin, Bull Acad Sci U.R.S.S., Class Sci chim., 1940, 727

20 N A Belozerskii and B A Freidlina, J appl Chem (USSR), 1941, 14, 466

21 Y Yamaguti and S Sisido, J chern SOC Japan, 1941, 62, 304

22 E R Natsvilishvili and A G Bergman, Bull Acad Sei, U.R.S.S., Class Sci chim., 1943, 23

23 E Ya Gorenbein, J Gen Chem (USSR), 1945, 15, 729

24 H Bloom and E Heymann, Proc R SOC., 1947, 188A, 392

25 E Ya Gorenbein, J Gen Chem (USSR), 1947, 17, 873

26 T G Pearson and J Waddington, Faraday SOC Discussion, 1947, No 1, 307

27 N M Tarasova, J phys Chem (USSR), 1947, 21, 825

28 E Ya Gorenbein, J Cen Chem (USSR), 1948, IS, 1427

29 I I Bokhovkin, ibid., 1949, 19, 805

30 E Ya Gorenbein and E E Kriss, ibid., 1949, 19, 1978

31 H Grothe, Z Elektrochem, 1949, 53, 362

32 I N Belyaev and K E Mironov, Dokl A M Nauk SSSR, 1950, 73, 1217

33 I I Bokhovkin, J Gen Chem (USSR), 1950, 20, 397

34 A Vayna, ANumhio, 1950, 19, 215

35 E Ya Gorenbein and E E Kriss, J phys Chem (USSR), 1951, 25, 791

36 R C Spooner and F E W Wetmorc, Canad J Chem., 1951, 29, 777

37 R W Huber, E V Potter and H W St Clair, Rep Invest U S Bur Mines, No 4858, 1952

38 J Byme, H Fleming and F E W Wetmore, Canad J Chem., 1952, 30, 922

39 J D Edwards, C S Taylor, L A Cosgrove and A S Russell, Trans electrochem SOC., 1953, 100, 508 Aluminium, 1938

Physical properties of molten salts 9-41

40 k Bogorodski, J Soc phys.-chim m e , 1905, 37, 796

41 IC Mori and Y Matsushita, Tetsu t o Hognne, 1952, 38, 365

42 L Shartsis, W Cams and S Spinner, J A m ceram Soc, 1953,36, 319

43 H Bloom, I W Knaggs, J J Molloy and D Welch, Trm Faraday Soc., 1953, 49, 1458

44 1 N Belyaev, Incest Sekt Fiziko-Khim Anal., 1953, 23, 176

45 P I Protsenko and N P Popovskaya, Zh obshch Khim, 1954, 24, 2119

46 P I Protsenko and N P Popovskaya, Z h f z Khim., 1954, 28, 299

47 K Sakai, J Chem SOC J a p w Pure Chem Sect., 1954, 75, 186

48 N P Luzhnaya and I P Verwhchetina, Izuest Sekt Fiziko-Khim Anal., 1954, 24, 192

49 I P Vereshchetina and N P Luzhnava, ibid., 1954, 25, 188

50 L Shartsis and H F Shermer, J Am c e r a SOC, 1954, 37, 544

51 V D Polyakov, I z w s t Sekt Fiziko-Khim Anal., 1955, 26, 147

52 P I Protsenko, ibid., 1955,26, 173

53 V D Polyakov, ibid, 1955,26, 191

54 K B Morris, M I Cook, C Z Sykw and M B Templeman, J A m chem SOC., 1955, 77, 851

55 T Baak, A c t a Chem Scand., 1955, 9, 1406

56 K Sakai and S Hayashi, J chem SOC Japan, Pure Chem Sect., 1955,76, 101

57 E R van Artsdalen and I S Yaffe, J phys Chem., 1955, 59, 118

58 Yu K Delimarskii, I N Sheiko and V G Fenchenko, Zh $2 Khim., 1955, 29, 1499

59 B S Harrap and E Heymann, Trans Faraday SOC., 1955,51, 259

60 G M Pound, G Derge and G Osuch, Trans Amer Inst Min Mer Eng., 1955,203,481

61 H C Cowen and H J Axon, ibid., 1956,52242

62 N P Luzhnaya, N N Evseeva and I P Vereshchetina, Zh neorg Khim, 1956, 1, 1490

63 K Mori, Tetsu t o Hagane, 1956,42, 1024

64 B M Lepinskikh, 0 A Esin and S V Sharrin, Zh priklad, Khin., 1956, 29, 1813

65 E W Yim and M Feinleib, J electrochem SOC., 1957, 104, 626

66 F R Duke and R A Fleming, ibid., 1957, 104, 251

67 J B Story and J T Clarke, Trans Amer Inst Min Met Eng., 1957, 209, 1449

68 V A Kochinashviii and V P Barzakovskii, Zh priklad Khim., 1957.30, 1755

69 W C Phelps and R E Grace, Trans Amer Inst Min Mer Eng., 1957, ZOS, 1447

70 S Okado, S Yashizawa, N Watanabe and Y Omota, J chem SOC Japan, Ind C h e m Sect., 1957,60, 670

71 F R Duke and R A Fleming, J electrochem SOC., 1958,105, 412

72 E Vatslavik and A I Belyaev, Zh neorg K h i m , 1958, 3, 1044

73 H R Bronstein and M A Bredig, J A m c h SOC., 1958,80, 2077

74 0 A Esin and V L Zyazcv, Izoest Akad Nauk, S.S.S.R., 1958, No 6, 7

75 K A Kostanyan, I z w s t Akad Nauk Armyan S.S.S.R., 1958, 11, 65

76 R H Moss, Unio Microfilms (Ann Arbor, Mich.), 1955, No 12, 730

77 Y Doucet and M Bizouard, Compt rend., 1960, 250, 73

78 B F Markov and V D Prusyazhnyi, Ukr khim Zh., 1962, 28, 653

79 Y Doucet and M Bizouard, Compt rend., 1959, 248, 1328

80 V P Mashovets and V I Petrov, Zh prikl Khim., 1959, 32, 1528

81 J O'M Bockris, J A Kitchener, S Ignatowitz and J W Tomlinson, Discuss Faraday SOC., 1948,4,265

82 P I Protsenko and 0 N Shokina, Zh neorg K h i m , 1960, 5, 437

83 P I Protensko and A Ya Malakhova, ibid., 1960, 5, 2307

84 L F Orantham and S J Yosim, J chem Phys., 1963, 38, 1671

85 A S Dworkin, H R Bronstein and M A Bredig, Discuss Faraday SOC., 1961, 32, 188

86 A S Dworkin, R A Sallach, H R Bronstein, M A Bredig and J D Corbett, J phys Chem., 1963, 67,

87 B F Markov and V D Prusyazhnyi, Ukr khim Zh., 1962,28, 268

88 R V Chernov and Yu K Delimarskc Zk neorg Khim., 1961, 6, 2749

89 A S Dworkin, H R Bronstein and M A Bredig, J phys Chem., 1963, 67,2715

90 H R Bronstein and M A Bredig, ibid., 1961,65, 1220

91 H R Bronstein, A S Dworkin and M A Bredig, J chem Phys., 1961, 34, 1843

92 V G Selivanov and V V Stender, Zh neorg Khim., 1959, 4, 2058

93 B F Markov and V D Prusyazhnyi, Ukr khim Zh, 196528, 130

94 B F Markov and V D Prusyazhnyi, ibid., 1962,28,419

95 8 R Bronstein, A S Dworkin and M A Bredig, J phys Chem., 196566, 44

96 G W Mellors and S Senderor, ibid., 1960, 64, 294

97 E R Buckle and P E Tsaoussoglou, Trans Faraday Soc., 1964,60,2144

98 M F Lantratov and 0 F Moiseeva, Zh $2 Khim., 1960, 34, 367

99 V V Rafal'skii, Ukr khim Zh., 1960, 26, 585

100 K B Morris and P L Robinson, J phys Chem, 1964, 68, 1194

101 P C Papaioannou and G W Harrington, ibid., 1964, 68, 2424

102 H Winterhager and L Werner, ForschBer Wirt.-u Verk Minist NRhein.-Westf, 1957, 438

103 K, B Morris and P L Robinson, J chem Engng Data, 1964, 9, 9, 444

104 L J Howell and H H Kellogg, Trans A m Inst Min Engrs, 1959, 215, 143

105 J O'M Bockris and G W Mellors, J phys C h e w 1956, 60, 1321

106 Yu C Samson, L P Ruzinov, N S Rezhemnukova and V E Baru, Zh fiz Khim., 1 9 6 4 , s 481

1145

9-42

The surface tension (rnNrn-’) at temperature t (“C) is given as y,, or the constants a, b and to in the equation

y,=a b(t-to) arc given for the temperature range r Principal references are in bold type

Physical properties of molten salts

Table 9.6 SURFACE TENSION OF PURE MOLTEN SALTS

Y900

Y95o

YlOOO

Y966 Y979

164 134.8 0.015

85

83

81 101.5

CdBr, Ref 16

CdCI, Ref 16

CsBr

Ref 28, 29

CSCl Ref 29,612

C s 2 S O 4

Ref 30

FeO Ref 28

GaCI, Ref 24

GaCI,

Ref 17

GeO, Ref 21

HgBrz

Ref 8

HgCI2 Ref 8

IF5 Ref 18

9226

78.46 73.47 64.77 53.17 92.5 0.069

414 421-597 114.25 98.84 83.75 584.0

56.6 0.18

170 166-170

Physical properties of molten salts 9-43 Table 9.6 SURFACE TENSION OF PURE MOLTEN SALTS-continued

0

(m.p + 10)- (m.p.+210) 151.47 132.87 114.27

107.6 0.080

435 445-501

108.61 102.21 92.61 79.81

193.54 171.94 150.34

143

130

116 162.41 134.51 106.61

560

137.14 123.22 109.30 250.46 228.60 206.74 115.4 0.053

255 276-425

223

216

209

202 101.9 0.105

170 170-220

NaSAIFs Ref 31

NaBr Ref 16, 6, 27

NaCl Ref 6, 27

NaF Ref 6, 31

NaI Ref 2l

NazMoO, Ref 30

NaNO, Ref 22, 27

NaNO, Ref 27

NaPQ,

Ref 6 30

Na2S04 Ref 13 6

Y l l O O

Y IO00 Yizoo Y1400 Yl500

YllOO YlZOO

Y l O O

Y l O O Yzoo

106

103

92

19 116.42 107.12 91.82 88.52 185.21 168.81 152.41 144.21 147.4

0.090

0

(m.p + 10)- (m.p.+210) 211.68 196.28 180.88 173.18 121.2 0.041

277 291-384 116.21 112.70 108.80 104.90 200.74 186.34 171.94 150.34

193

190

186

183 201.46 182.0 162.46 143.0 137.12 126.12 115.12

60

58

54 99.77 88.17 76.57

9-44

Table 9.6 SURFACE TENSION OF PURE MOLTEN SALTS-continued

Physical properties of molten salts

1 A GradenwiQ Ann Physik., 1899,61,467

2 2 Motylewski, Z anorg Chem., 1904, 38, 410

3 R Lorenz and F Kaufler, Ber dt chem Ges., 1908,41, 3727

4 R Lorenz and A Liebmann, 2 phys Chem, 1913,83,459

5 R Lorenz, A Liebmann and A Bochberg, 2 anorg Chem., 1916,94,301

6 F M Jaeger, Z anorg Chem, 1917,101, 1

7 H V Wartenberg, G Wehner and E Suran, Naehr Ges Wiss Gottingen, 1936, 2, 65

8 E B R Prideaux and J R Jarrett, J chem Soc., 1938,1203

9 V P Banakovskii, Bull mad sci URSS Classe sci chim, 1940, 825

10 P P Kozakevich a n d k F Kononenko, J phys Chem (USSR), 1940,14,1118

11 K Semenchenko and L P Shikhobolova, ibid, 1947,21,613

12 K Semenchenko, ibid., 1947,21,707

13 K Semenchenko, ibid., 1947, 21, 1387

14 A Vajna, Alluminio, 1951, 20, 29

15 J S Peake and M R Bothwell, J Am chem Soc., 1954, 76, 2625

16 N K Boardman, A R Palmer and E Heymann, Trans Faraday Soc., 1955,51,2?7

17 N N Greenwood and K Wade, J inorg nuclear Chem, 1957,3,349

18 M T Rogers and E E Carver J Phys Chem., 1958,62,952

19 J L Dah1 and F R Duke, US Atomic Energy Comm, 1958, ISC-923

20 R B Ellis, J E Smith and E B Baker, J phys Chem., 1958,62, 766

21 W D Kingery, 3 Am ceram Soc., 1959,42, 6

2 2 C C Addison and J M Coldrey, J chem SOC, 1961,468

23 I D Sokoiova and N K Voskresenskaya, Zh prikl Khim., 1962,36, 955

24 N N Greenwood and I J Worrall, 3 chem Soc., 1958, 1680

25 V B Lazarev and M N Abduaalyamova, Izv Akad Nauk SSSR, Ser Khim., 1964,1104

26 B M Lepinskikh, 0 A Esin and G A Teterin, Zh neorg Khim, 1960,5,642

27 H Bloom, F G Davis and D W James, "bans Faraday Soc., 1960,56, 1179

28 0 K Sokolov, Izv A h d Nauk SSSR Mer G o m Delo, 1963, 4, 59

29 R B Ellis and W S Wilcox, Work performed under U S At Energy Comm; T-10-7622,1962, pp 128-36

Physical properties of molten salts 9-45

30 ‘International Critical Tables’, McGraw-Hill, New York, 1933

31 H Bloom and B W Burrows, ‘Proc 1st Australian Cod Electrochem’ (J A Friend and F Gutman eds),

32 S D Gromakov and A I Kostromin, Uniu in V I UP Yanma-Leninn Khim, 1955,115.93

p 882 Pergamon Press, Oxford, 1964

Table 9.7

The surface tension (mN m - ’) at temperature t(“C) and composition p(wt.”/,) of the first-named constituent is given as

yt (or cr, ), or the constants a, b and t o in the equation y, = a - b(t - t o ) are given for the temperature range r Principal

references are in bold type

SURFACE TENSION OF MOLTEN BINARY SALT SYSTEMS AND OTHER MIXED IONIC MELTS

O600

P b700

0 7 5 0

P

~ 1 0 0

P 0’500

0

24.1

119

115 27.8 134.0 0.077

0

-

2.5

142 5.6

598 2.5

liquidus-e 400 33.3 60.0

116 53.5 77.7 136.9 143.4 0.073 0.070

133

130 70.3

104

101 72.6

123

117 43.7

150

142 88.8 148.4 0.072

0

15

118

1.5 I34

84.0

155

152 76.2

141

138 86.3

113

110 88.6

136

129 67.4

9-46

TaMe 9.7

continued

Physical properties of molten salts

SURFACE TENSION OF MOLTEN BMARY SALT SYSTEMS AND OTHER MIXED IONIC MELTS-

302

297 51.5

303

292 20.5

235

221 55.7

247

237 29.4

115

100

5

150 5.5

555 20.9

176

150

140 65.6

160

149 87.1

235

232

238 47.4

117

111 44.8

121

108

10

152 15.4

543 41.3

87

96 75.3

140

143

142 92.0

120

121

125 85.8

130

134 50.9

184

179

185 59.0

573 61.7

81

87

95 84.9

107

112

118 95.5

163

158 78.1

133

126 88.3

81

88

% 94.8

161

159 93.4

Physical properties of molten saks 9-47

Table 9.1 SURFACE TENSION OF MOLTEN BINARY SALT SYSTEMS AND OTHER MIXED IONIC MELTS-

0

48.5 124.3 0.070

0

43.1 130.5 0.068

0

47.2 166.1 163.8 90.5

555 68.1

409 81.9

liquidus-c 400 67.6 87.3 127.3 123.4 0.074 0.072

tiquidus-c 400 54.0 69.0 165.1 144.3

0

0 129.9 0.055

0

23.9

222

219 92.9

134 6.1

182 145

178 142

173 135 16.4 34.4

-

(mp + lO)-(m.p.+210) 2.7 14.8

183 153 5.5 15.2

125 118

114 109 5.8 11.5

177 157 35.8 55.9 131.3 130.6 0.061 0.055

(m.p.+ lO)-(rn.p.+ZlO)

329 59.5 127.9 129.6 0.056 0.062

139 141 7.8 12.8

128

123

116 54.1

85

78

71 65.6

111

107

104

49.0 124.4 0.063

0

34.2

129 28.6

117

107 28.0

127 77.0 131.8 0.052

0

81.5 133.6 0.070

93

86

79 83.6

104

101

73.2 127.2 0.069

0

-

100

92 51.7

Physical properties of molten salts e 4 9 TSbk 9.7

311

316 13.5 130.0 0.075

0

-

16.1 132.5 0.076

0

75.9 86.9

113 118 17.8 23.9

315 328

317 328

317 328 31.8 58.3 129.6 125.0 0.074 0.059

105

97

92 33.0

110 0.8

108

10.1

119 1.1

167

35.4 127.1 0.035

91.9

119 27.8

(mp + 10)- (m.p + 210) 36.5 63.4 133.7 135.4 0.073 0.068

9-50 Physical properties of molten salts

Table 9.7 SURFACE TENSION OF MOLTEN BINARY SALTS SYSTEMS AND OTHER MIXED IONIC MELTS-

-

-

104 65.1

234

235 15.3

92 28.5 10.3

128 39.1 200.1 197.1

173 62.8

112

107

104 69.9

232

230 39.6

135 38.6 10.4

142 43.9 192.7 188.8

171 69.0

112

107

104 75.7

217

221

223 52.8

168 58.4 10.4

150 49.5 188.0 183.5

169 83.1

116

111

107 82.5

199

204

209 65.4

174 60.0 10.1

190 59.5 175.1 173.4 170.9

50.0

295

284 8.6

162 90.3

124

118

113 84.7

192

196

79.0

205 68.5 10.6

210 67.3 155.0 146.3

174 134

179 145

183 158 85.1 92.1

202 192 80.0

1 E Elchardus, Compf rend., 1938,206, 1460

2 C W Parmelee and C G Harman, Unio Illinois Eng Exprl Sra Bull., 1939, No 311, 29

3 V P Barzakovskii, & I 1 mad sci U.R.S.S., Classe sci chim, 1940, 825

4 P P Kozakevich and A F Kononenko, J phys Chem (USSR), 1940, 14, 1118

5 K Semenchenko and L P Shikhobolova, ibid., 1947,21,613

6 K Semenchenko, ibid., 1947, 21, 707

7 K Semenchenko, ibid., 1947, 21, 1387

8 L Shartsis, S Spinner and A W Smock, J Am ceram SOC., 1948, 31, 23

9 L Shartsis and R Canga, J Res Nut Bur Stand, 1949, 43, 221

10 S Carlen, Trans Chalmers Unio Tech Gottenburg, 1949, No 85

11 A Vajna, Alluminninio, 1951, 20, 29

12 L Shartsis and S Spinner, J Res N a f Bur Stand., 1951, 46, 385

13 L Shartsis and W Capps, J Am ceram Soc., 1952,35, 169

14 L Shartsis and H F Shermer, ibid., 1954, 37, 544

15 J S Peake and M R Bothwell, J Am chem Soc., 1954,76,2656

16 N K Boardman, A R Palmer and E Heymann, Trans Faraday SOC., 1955, 51, 277

17 0 G Desyatnikov, Zh priklad Khim, 1956, 29, 870

18 J H Dah1 and F R Duke, J phys Chem, 1958,62, 1498

19 G Bertozzi and G Sternheim, ibid., 1964,68, 2908

20 I D Sokolova and N K Voskresenskaya, Zh prkl K h i m , 1962, 36, 955

21 A A Appen and S S Kayalova, Dokl Akad N u u k , SSSR, Ser jr Khim., 1962, 145,592

22 C F Callis, J R Van Wazer and J S Metcalf, J Am chem Soc., 1955,77, 1468

23 B M Lepinskikh, 0 A Esin and G A Teterin, Zh neorg Khim, 1960,5, 642

24 H BIoom, F G Davis and D W James, Trans Faraday SOC., 1960, 56, 1179

Physical properties of molten salts 9-51

T a b 9.8 VlSCOSITy OF PURE MOLTEN SALTS

The viscosity (centipoise) at tempmature t(“c) is given as qn or the constants a and b in the equation

log qr -0 +b/(t .I 273) are given for the tempwature range r Principal references are in bold tyjw

240 2.20 158ooo

25 100

6 300

2000 4.506

32

23

18 3.021 1.870

1248 2.60 2.35 2.10 2.35 1.85 1.55

280 1.95 1.40 2.196 2.008 1.843 1.768 1.738 1.694 1.600

1.543

2.669 2.244 1.995 1.715 1.458 1.150 1.022 0.831

1.094 0.841

0.673 13.79 9.665

7.091

KI Ref 30

KN02 Ref 33

KN03 Re€ 27, 16, 31,34, 35

KOH

Ref 10

LiBr Ref 7, 14

LiI

Ref 14

UNO3 Ref 17, 12, 11, 3

Na3AlF6 Ref 19

NaBr Ref 14, 16

NaCI Ref 16, 34, 35

NaI

Ref 30

NaNO, Ref 33

NaN03 Ref 31,34, 36, 37

NaOH Ref 10

NaPO, Ref 28, 4

PbBr, Ref 22, 17, 1

PbCI2 Ref 2 5 1

TINO, Ref 33

960 418-450

2705 2.090 1.673 1.163

2.3

1.3 0.8 1.815 1.096 0.757 2.50 1.70 1.30 5.5

4.0

2.9 6.7 6.5

6.0

1.345 1.332 1.288 1.463

I a09

0.737 1.581 1.168 0.818

- 1.07

868 282-310 3.156 1.901 1.305 4.0

2.8

1.9

- 1.04

565 207-250

9-52

REFERENCES TO TABLE 9.8

Physical properties of molten salts

1 R Lorenz and H T Kalmus, Z phys Chem, 1907,59,244

2 V T Slavyanskii, Dokl Akad Nauk SSSR, 1947,58,1077

3 H M Goodwin and R D Mailey, Phys Rev., 1908,26, 28

4 K Amdt, Z chem Apparat., 1908, 3, 549

5 A H W Aten, Z phys Chem, 1909, 66, 641

6 G J J a m and R D Reeves Advan electrochem Eng., 1967,s

7 S Karpachev and A Stromberg, Zh Fiz Khim, 1938, 11, 852

8 R S Dantuma, Z anorg allgem Chem., 1938,175,l

9 R Lorenz and A Hoechberg, Z morg Chem, 1916, 94, 317

10 K Arndt and G Ploetz, Z phys Chem., 1926, 121,439

11 E van Aubel, Bull sei acad roy Belg., 1926, 12, 374

12 R S Dantuma, Z anorg allg Chem, 1928, 175, 1

13 G Jander and K Brodemon, 2 anorg allgem Chem, 1951, 264, 57

14 I G Murgulescu and S Zuca, Z physik Chem (Leipzig), 1961,218,379

15 A G Stromberg, Zh Fiz Khim, 1939,13,436

16 C E Fawsitt, Proc roy Soc (London), 1908,93

17 K S Evstropev, Akad Nauk SSSR., Otdel Tekh Nauk Inst Mash Sou., 1945,3,61

18 H Bloom, B S Harrap and E Heymann, Proc R SOC., 1948, A194, 237

19 A Vajna, Allum'nio, 1950, 19, 133

20 L Shartsis, W Capps and S Spinner, J A m cerm Soc., 1953,36, 319

21 F A F'ugsley and F E W Wetmore, Canad J Chem, 1954,32, 839

22 B S Harrap and E Heymann, Trans Faraday Soc., 1955.51.259

23 B S Harrap and E Heymann, ibid., 1955,51,268

24 J D Mackenzie, ibid., 1956, 52, 1564

25 N P Luzhnaya, N N Evseeva and I P Vereshchetina, Zh neorg Khim, 1956, 1, 1490

26 S Karpachev, Zh Obshch Khim., 1935, 5, 625

27 R Lor= and T Kalmus, Z Physik Chem, 1907, 59,244

28 G G Nozadze, Soobshch Akad Nauk Gruzin S.S.S.R., 1957, 19, 567

29 J P Frame, E Rhodes and A R Ubbelohde, Trans Faraday Soc., 1959, 55, 2039

30 I G Murgulescu and S Zuca, Rev Roumaine Chim., 1965,10,123

31 H M Goodwin and R D Mailey, Phys Rev., 1906,23, 22; ibid., 1907, 25,469; ibid., 1908, 26,28

32 G J Janz and J D E McIntyre, J electrochem Soc., 1962, 109, 842

33 J P Frame, E Rhodes and A R Ubbelohde, Trans Faraday Soc., 1959,55,2039

34 R S Dantuma, Z Anorg allgem Chem., 1938, 175, 1

35 K Ogawa, Nippon Kinzoku Gakkaishi, 1950, 14B, 49

36 R Lorenz and H T Kalmus, 2 physik Chem, 1907,59, 17

37 C E Fawsitt, Proc roy Soc (London), 1908, A80,290

Table 9.9 VISCOSITY OF MOLTEN BINARY SALT SYSTEMS AND OTHER MIXED IONIC MELTS

The viscosity (centipoise) at temperature t("C) and composition p(wt.Y> of the first-named constituent is given as qr,

or the constants a and b in the equation log q, = a + b / ( t + 273) are given for the temperature range r Principal

references are in bold type

Physical properties of molten salts 9-53

TaMe 9.9 VISCOSITY OF MOLTEN BINARY SALT SYSTEMS AND OTHER MIXED IONIC MELTS contimred

-

-

I

- 5.8 2.5 6.5 2.5 6.9 44.5

2 750

980

-

- 61.6 6.8 x lo5

200

1.75 31.7

19 500

10 ooo

0 1.59 1.00 0.70

2 5 6.9

-

-

25.7 9.6 6.4 5.2 4.8 13.8 2.3 2.3 41.9

-

-

- 7.4 5.1

5 6.3

5 6.9 49.2

30 900

6 170

1900

- 70.6 5.1 x lo6

4 680

960

- 87.1

3 020

520

-

- 69.2 3.1 x lo6

202 46.1

11OOo

2 140

1250 17.4 1.65 1.16 1.00

5 7.0

47.9 13.6 8.6 6.5 5.5 19.9 7.4 2.4 52.8

-

-

- 6.4 4.8

10 5.7

10 7.1 54.9

282 2.50 2.36 53.1

3 200

850

530 44.8 2.59 2.11 1.79

10 7.3

67.4 19.6 12.6 8.7 7.0 27.2 7.0 2.2 62.7 18.2 8.9 5.6 4.1

15 4.8

15 10.9 59.7

35 500

9 550

3710

1 260 89.0

3900

1 290

450 95.5

355 OOO

3 630

980

320 85.8 1.9 x lo6

1 700

540

400 65.5 3.49 2.95 2.60

15 8.0

35.9 19.5 5.6 1.9 71.6 19.1 9.6 6.0 4.3

5 130

2400

1 120 97.2

141 OOO

7 240

3090

1440 94.4

272 71.7

190

150 88.3 4.36 3.69 3.31

-

46.6 13.8 4.2 1.8 79.7 18.1 9.2 6.4 4.6

-

100 4.92 4.22 3.74

562 9.6 3.2 1.4 83.5 8.9 6.0 4.5

100

21 400

11 500

6 460 1.6 x 105

84.4 3.85 3.28 3.05

-

9-54

Table 9.9 VISCOSITY OF MOLTEN BINARY SALT SYSTEMS AND OTHER MIXED IONIC MELTS-conrinued

PhysicaZ properties of molten salts

200

37.6 3.26

610

360

280

85 4.8 1.4 3.20 2.57

206 1.72 30.4

50 100

8 320

3 890

2 040 35.5

460

270

210

90 5.9 2.8 3.27 2.67 2.21 1.91 32.0 3.19 -0.63

271 1.80 1.27 26.8 3.50 2.47 1.88 58.9 2.78 1.51

- 79.3 1.07 0.8 1 8.8 3.66

227 1.56 15.9

-

-

-

24 OOO 21.8

12000

2 190

1120

710 36.2

350

200

180

95 6.4 4.2 3.68

279 2.32 1.98 36.0 2.45

21 71.9 2.62 1.73 1.24

825

284 1.88 1.39 37.9 3.36 2.38 1.85 59.9 2.69 1.70

-

-

100

1.13 0.89 18.3 3.34 2.06 1.42 23.9

250

150

120 97.5 6.7 5.7 2.83 2.18 1.96 39.6 0.1 1

226 1.85 69.1 1.44 0.99

-

-

21.8 3.37 2.10 1.47 29.9

15 100

1350

200

- 28.9

510

300

200 41.4

88.8

3.17 2.15 1.57

100

2.31 1.83

100

2.31 1.90 78.8

100 2.31 1.83

4 570

355

47

- 37.9

1.00

741-1 013 707-1 001 657-1 017 822-1 002 942-1 064 1030-1 077 995-1 070

Physical properties of molten salts 9-55

Tzble 9.9 VISCOSITY OF MOLTEN BINARY SALT SYSTEMS AND OTHER MIXED IONIC MSLTS conrinurd

1 C L Babcock, J Am ceram SOC., 1934, 17, 329

2 S Karpachev and k Stromberg Z anorg allg Chem., 1935, 222, 78

3 J R Rait and R Hay, J R Tech Coll (Glusgow), 1938, 4, 252

4 E Preston, J SOC Glass Tech., 1938, 2 2 45

5 V P Barzakovskii, Bull Acad Sci URSS, Classe, sei chim., 1940, 825

6 H Bloom, 8 S Harrap and E Heymann, Proc R SOC., 1948, A194, 237

7 A Vajna, Alluminio, 1950, 19, 133

8 L Shartsis, S Spinner and W Capps, J Am ceram Soc., 1952 35, 155

9 L Shartsis, W Capps and S Spinner, ibid., 1953, 36, 319

10 L Shartsis, S Spinner, and H F Shermer, ibid., 1954, 37, 544

11 J O M Bockris and D C Lowe, Proc R Soc., 1954, A226 1167

12 B S Harrap and E Heymann, Trans Faraday SOC, 1955, 51, 259

13 B S Harrap and E Heymann, ibid, 1955, 51, 268

14 V D Polyakov, Izuest Sekt Fiziko-Khim Anal., 1955,26, 147

15 V D Polyakov, ibid., 1955, 26, 191

16 J OM Bockris J D Mackenzie and J A Kitchener, Trans Faraday SOC., 1955,51, 1734

17 N P Luzhnaya, N N Evseeva and I P Vereshchetina, Zh nemg Khim., 1956, 1, 1490

18 G G Nozadze, Soobshch Akad Nauk Gruzin SSSR, 1951,19;567

19 I P Vereshchetina and N P Luzhnaya, Zm Sekt fiz.-khirn Analizu, 1954, 25, 188

20 C F CaIlis, J R Van Wazer and J S Metcalf, J Am chem Soc., 1955, 77, 1471

21 G J Jam, ‘Molten Salts Handbook’, Academic Press, London, 1967

IO Metallography

Metallography can be defined as the study of the structure of materials and alloys by the examination of specially prepared surfaces Its original scope was limited by the resolution and depth of field in focus by the imaging of light reflected from the metallic surface These limitations have been overcome by both transmission and scanning electron microscopy (TEM, STEM and SEM) The analysis of X-rays generated by the interaction of electron beams with atoms at or near the surface, by wavelength or energy dispersive detectors (WDX, EDX), has added quantitative determination of local composition, e.g of intermetallic compounds, to the deductions from the well-developed etching techniques Surface features can also be studied by collecting and analysing electrons diffracted from the surface A diffraction pattern of the surface can be used to determine its crystallographic structure flowenergy electron diffraction or LEED)

These electrons can also be imaged as in a conventional electron microscope (low-energy electron microscopy or LEEM) This technique is especially useful for studying dynamic surface phenomena such as those occurring in catalysis X-ray photoelectron microscopy (XPS or ESCA) now enables the metallographer to analyse the atoms in the outermost surface layer to a depth of a few atoms (0.3-5.0nm) and provides information about the chemical environment of the atom Auger spectroscopy uses a low-energy electron beam instead of X-rays to excite atoms, and analysis of

the Auger electrons produced provides similar information about the atoms from which the Auger electron is ejected

Nevertheless, the conventional optical techniques still have a significant role to play and their interpretation is extended and reinforced by the results of the electronic techniques

The final machining operation should be done with a single sharp tool, for instance by planing, turning or milling with a fly-cutter, rather than by the use of a milling cutter For soft metals (e.g copper, lead, pure aluminium) the shape of the tool is important; it should have a rounded nose

and adequate front clearance to prevent rubbing, and it should have a large top rake (the softer the metal, the larger the rake required) so that it presents almost a chisel edge to the specimen For harder metals more orthodox tools may be used

Illumination of unetched specimens for photomacrograph to show porosity requires a broad source of illumination The sky (without direct sunlight) is sometimes the most suitable sotlrce

Etching reagents for macroscopic work are listed in Table 10.1 Directions for ‘sulphur-printing’,

to show the distribution of sulphide in steel, are included

10.2 Microscopic examination

Metallographic specimens are normally prepared for examination under the microscope by cutting out the piece to be examined (preferably not more than 3 cm dia.), carefully removing the disturbed surface layer (by turning or filing with a sharp tool) and then rubbing the surface with successively finer abrasives until a smooth polished surface is obtained, sensibly free from

10-1

10-2 Metallography

disturbing effects from the cutting and grinding; the clean, smooth, undistorted surface is then attacked chemically, or otherwise, by etching reagents which reveal the structure of the metal Any mechanical method of cutting or smoothing the surface produces distortion of the metal near the surface, and it may produce local heating; the objective is to make the disturbed layer succes- sively thinner at each stage until it is negligible or can be removed by etching The thickness

of the disturbed layer is in the range 10-100pm for emery or silicon carbide papers with hand grinding Some or all of the mechanical grinding and polishing can often he replaced by chemical of electrochemical polishing methods, by which the metal is attacked in such a way that protuberances are preferentially dissolved and the flat undisturbed metal surface is laid bare, usually with a saving of time and frequently with an improvement in result

For some purposes, e.g study of slip processes involving individual dislocations, electron microscopical studies of fine structure, and quantitative microhardness testing under light loads, electro-polishing is almost indispensable In general, the type of finish required varies somewhat with the magnification to be used in examination High-power examination demands great perfection of small areas, but relatively largescale undulations, such as may sometimes occur on

electropolished specimens, are unimportant At lower powers detail may be less important, but widely spaced imperfections and undulations are liable to become obtrusive

Table 10.1 ETCHING REAGENTS FOR MACROSCOPIC EXAMINATION

A Aluminium base

1 Aluminium (a) Concentrated Keller’s

and its alloys Reagent

Nitric acid (1.40) lOOml Hydrochloric acid (1.19) 50ml Hydrofluoric acid (40yJ lpml (b) Nitric acid (1.40) 30ml

Hydrochloric acid (1.19) 30mI 2% conc hydrofluoric 30ml acid

Nitric acid (1.40) 15ml Hydrochloric acid (1.19) 45ml Hydrofluoric acid (40%) 1Sml

in water

(c) Tucker’s Reagent

(d) 10% sodium hydroxide

2 U ~ l l o y e d (e) Flick’s Reagent

aluminium and Hydrochloric acid 15ml

AkCn alloys Hydrofluoric acid lOml

3 Aluminium- (f ) Hume-Rot hery’s Reagent

silicon Cupric chloride 15g

4 Aluminium- (9) Keller’s Reagent

copper 297 nitric acid (1.40)

hydrochloric acid (1.19)

:% hydrofluoric acid (40%)

Rem water

5 Aluminium- (h) 5% cupric chloride

magnesium 3% nitric acid (1.40)

Rem water

copper-silicon (i) Nitric acid (1.40) 15ml

Hydrochloric acid (1.19) lOml Hydrofluoric acid (40%) 5ml

copper- Hydrochloric acid (1.19) 20ml

nickel Hydrofluoric acid (40%) Sml

6 Aluminium- (g) Keller’s Reagent (as above)

7 Aluminium- (j) Zeerleder’s Reagent

magnesium- Nitric acid (1.40) 15ml

Remarks

Can be diluted with up to 50ml water

Widely applicable, but very vigorous

nitric acid in water More frequently used as micro-etch

Clear surface with strong nitric acid

Microscopic examination 10-3 T8bk 10.1

Material Reagent* Remarks

ETCHING REAGENTS FOR MACROSCOPIC EXAMINATlOWontinued

Hydrochloric acid (1.19) 2ml Acid aqueous ferric chloride

Ferric chloride 25 g Hydrochloric acid (1.40) 25ml

A 1% mercuric nitrate

in distilled water

B 1% nitric acid (1.40) in water Mix A and B in equal proportions Chromium trioxide 40g Ammonium chloride 7.5g

Nitric acid (1.40) 50ml Sulphuric acid (1.84) 8ml

Distilled water IOOml Ferric chloride 59 g

So”/, hydrochloric acid

in water (b) 20% sulphuric acid in water

25% nitric acid in water 10% ammonium per-

sulphate in water Stead’s Reagent Cupric chloride l o g Magnesium chloride 4Og

Hydrochloric acid (1.19) 20ml Alcohol t o 1 litre

Fry’s Reagemt Cupric chloride 9og Hydrochloric acid 120ml

Humphrey’s Reagent Copper ammonium 120g chloride

Hydrochloric acid (1.19) 50ml

(h) 5-10% nitric acid in alcohol

(j) Sulphur-printing 3% sulphuric acid in water

Avoid use of water for washing or staining r a y result Use alcohol or acetone instead Grain contrast

(a) and (b) require moderately high standard of surface finish

A rapid ctch suitable for rmghly prepared

surfaces Addition of a trace of silver nitrate

( 5 % ) enhances contrast

To reveal strains in brasses

Time required to induce cracks is indication of residual stress

Good for alloys with silicon and silicon bronzes

Use hot (70-80T) for up to 1 h Shows segrega-

tion, porosity, cracks useful for examination

of welds for soundness Use hot (80°C) for 10-20min Scrub lightly to remove carbonaceous deposit Purpose as (a) Mixtures of (a) and (b) are also used similarly Purposes as (a) and (b) May be used cold if more convenient

Grain contrast etch Apply with swab Reveals grain growth and recrystallization at welds For revealing phosphorus segregation and pri- mary dendritic structure of cast steels Dissolve the salts in the acid with addition of a minimum

of water Phosphorus segregate unattacked, also eutectic cells in cast iron

To reveal strain tines in mild steeL Heat specimen

t o 150-250°C for IS-30min before etching Etch for I-3min while rubbing with a soft cloth Rinse with alcohol

Reveals dendritic structure of cast steels First treat surface with 8% copper ammonium chloride solution and then with (9) for f-1ih Remove copper deposit (loosely adherent), dry

and rub surface lightly with abrasive

Etch for up to +h Reveals cracks and carbon segregation More controlled than aqueous acids

Soak photographic printing paper in the acid and remove surplus acid with blotting paper Lay paper face down on the clean steel surface and

*Acids are concentrated, unless otherwise indicated e.g with specilk gravity

10-4 Metallography

Table 10.1

ETCHING REAGENTS FOR MACROSCOPIC EXAMINATIOlrl-eontimred

solution of sodium thio- sulphate Sodium meta- l g

bisulphite (can be increased for contrast)

(a) Russell‘s Reagent

A 8Oml nitric acid (1.40)

in 220ml water

B 45 g ammonium moly- bdate in 300ml water (b) Ammonium molybdate log Citric acid 25 g

Reagent Acetic acid, 75 ml

glacial ‘100 vol.’ 25 ml

hydrogen peroxide (c) Worner and Worner’s

(a) Picric acid (64YJ satu-

Water (d) Glacial acetic acid

‘squeegee’ into close contact After 2min remove

paper, wash it and fix in 6% sodium thiosulpbate

in water Brown coloration on the paper indicates

local segregation of sulphides

See p 10.38, Lead in steels Analogous to sulphur- printing

Austenitic steels High temperature steels FeCr-Ni casting alloys Also shows depth of nitriding

Good surface preparation needed Steel cast- ings Darkens Fe-rich areas, reveals segregation and primary cast structure

Phosphorus distribution in cast steel and cast iron Grain contrast

Grain contrast etch; removes deformed layer Mix equal parts of A and B immediately before use Swab for 10-30s

Rinse in water Bright etch revealing grain structure, defects, etc

Chemical polish revealing defects, etc

Specimen must be dry and water content of solution as low as possible

N.B.-Avoid all heating, as lead alloys recrystal- lize very readily

Immerse 5-10 min Grain contrast, laminations, welds Up to 50% nitric acid can be used Macrostructure of alloy with Ca, Sb and Sn Use fresh only Several minutes needed

2-10s by swabbing Good for alloys with Bi, Te

General defects; flow lines, segregation Etch for

Microscopic examination 10-5

Table 10.1 ETCHING REAGENTS FOR MACROSCOPIC EXAMINATlON-continued

Hydrochloric acid (1.19) 75ml

Sat soln of ammonium polysulphide in water (wipe off surface film) Hydrochloric acid (1.18) 2ml

Concentrated hydro- chloric acid (1.19) 5% hydrochloric acid

in alcohol Sodium sulphate 1.5g (3.5 g if hydrated)

Chromium trioxide 20g

Hydrochloric acid (1.18) 5Oml Nitric acid (1.M) 20 ml Hydrofluoric acid (40%) 30ml Hydrochloric acid (1.19) 30ml Nitric acid (1.40) 15ml

Hydrofluoric acid (40%) 30ml

Nitric acid (1.40) 30-

45 ml Hydrofluoric acid (40%) lOml

45 ml

Hydrochloric acid (1.19) 66ml Nitric acid (1.40) 34 ml

As (a) See a h ref 1 p 10.69

Grain structure; suitable most tin alloys (etch- ing time 20-30min)

S n S b alloys (up to 3min)

Good grain contrast HCI can be increased to 50% Wash under

running water to remove reaction products

Better than above for Zn-Cu alloys

Platinum metals group, especially Ru, Os, Rh

Cr, Mo W, V, Nb, Ta

Highly alloyed Ti, Hf, Zr; also Cr, W, Mo, V

Gold, platinum, palladium Used for cobalt alloy

if added to 34ml water

Dilute Ti, Hf and Zr alloys

Silver (Note: for safety methanol must be used It

is dangerous to add more than 5% nitric acid to ethanol)

Be and its alloys, especially for large grain sizes

Cobalt alloys

k i d s arc concentrated, unless otherwise indicated, e.& with specific gravity

10-6 Metallography

The most frequent novices’ errors are to fail to remove completely the distorted metal beneath the original cut surface, to change the structure by overheating the specimen, to carry abrasives over (by lack of cleanliness) from a coarse stage of grinding or polishing to a finer one, and to

develop false structures by staining through faulty drying after etching Preparation of an

unfamiliar material must be checked by repeated etching and repolishing to see that the structure remains constant as more metal is removed

The early stages of preparation are common to most metals and types of specimen Fine polishing may have to be varied to suit the metal Etching is peculiar to the metal under examination and the feature of the structure to be investigated

MOUNTING

Specimens of irregular shape, great fragility or very small size are best mounted in plastic Several specimens, if of similar materials, may be prepared in the same mount, with a saving of time For critical work a first-class finish is easiest to obtain on a rather small specimen, and this is best mounted for ease of handling except when electrolytic or chemical polishing is used Edgesections (e.g sections through plated coatings) must almost inevitably be mounted

The basic method is to place the specimen face-down in a die, cover it with plastic and apply the treatment needed to make the plastic set The mount is conveniently 2-3 cm in dia x approx 1 cm high Thermosetting, thermoplastic and cold-setting plastics are used Very hard materials (especially tungsten wires) are sometimes mounted in low-melting-point glass In many labora- tories the majority of specimens are mounted

It is essential to verqy that the structure of the metal will not be materially affected b y any heat and pressure applied in forming the mount Some ‘cold-setting’ plastics become hot while setting Some plastics used, with their characteristics, are listed in Table 10.2

Table 10.2

PLASTIC USED FOR MOUNTING

Phenolic (e.g ‘Bakelite’)

Thermosetting

Needs controlled heat and pressure Sufficiently inert to most solvents Normal grades good for general work but have high shrinkage; mineral-filled type (Bakelite x 262/2) preferable for

edge-sections If curing insufficient, e.g too low a temperature, the mount is soft and is attacked by acetone

Needs controlled heat and pressure Gives clear mount Attacked by acetone Rather soft

Two-ingredient version Polymer +catalyst +monomer Can be used as casting resin, cold-setting resin with some pressure or

warm-setting resin with pressure Several ingredients to be mixed for each batch, but gives good mounts without heat or pressure Inert to usual solvents

‘Araldite’ Grade D, a liquid casting resin, gives good mounts without heat or pressure Inert to usual solvents

For vacuum impregnation of oxide films, etc (see text)

Low shrinkage Inert t o usual solvents but attacked by glacial acetic acid’

Needs controlled heat (13&140°C) and pressure Low

shrinkage good polishing characteristics3

* Must be cooled under pressure to low temperature to solidify before ejection

Thermoplastics, such as polymethyl methacrylate, and thermosetting resins, such as ‘Bakelite’, are convenient for routine work because they are available as powders immediately ready for use, but they require a press, and normally only one size of cylindrical mount would be available Cold-setting resins may be formed simply in a container consisting of a short piece of tube

standing on a glass plate, and are therefore suitable for occasional use and odd shapes and sizes

To examine a surface critically in section, support it if possible by plating (eg with copper or nickel) by applying an evaporated coating, or by wrapping with aluminium foil and mounting

Microscopic examination 10-7

under pressure (this method is useful for measuring the thickness of anodic or similar transparent films) Fragile oxide or other films may be held together by vacuum impregnation: use a vacuum desiccator and tap funnel to run resin varnish round the specimen in a rough vacuum (e.g at

about 10 torr residual pressure), remove the specimen and container to an oven (at 8O'C for

Bakelite grade NPA) and heat until the resin is polymerized A similar technique may be used with casting resins (if sufficiently fluid) which set without heat, although impregnation is liable to be less effective than with the very fluid hot varnish

GRINDMG

Emery or silicon-carbide cloths and papers are normally used Silicon carbide is preferred because

it is harder, has sharper particles and cuts at a faster rate Use strips 20-30 cm x about 8 cm laid

flat on plate glass, and rub the specimen to and fro on the strip Start with not finer than 80 grit,

and rub until all traces of saw cuts are removed Turn the specimen through 90" and mb until the

first set of emery scratches are removed Repeat at least once, because the depth of the deformed layer is several times the depth of the residual scratches Then progress to the next finer paper or cloth, turning the specimen through W, and again rub until the previous scratches are removed, then to the next finer paper similarly, until grade 600 silicon carbide paper is reached or, for softer

alloys such as aluminium, the finest emery paper is reached (usually grade 4/0, but grade 6/0 is sometimes useful) A fine paraffin oil (e.g 'white spirit') should be flooded over the papers to act as

a lubricant, or they should be continuously washed with water or white spirit For soft metals, a more viscous liquid paraffin is preferred to avoid pick-up of silicon carbide or emery in the surface

of the specimen Slowly rotating silicon carbide discs continuously washed with water are frequently used

For very hard metals diamond hones4 and lapsio6 have been used for grinding

Metals containing constituents of widely differing hardness may develop undesirable relief when ground on fine papers An alternative is to use a lead lap Lead foil is stretched over a glass plate and is flooded with white spirit Fine abrasive (e.g alumina) is worked into the surface by placing some on the wet surface and working it in with a steel disc Any loose abrasive remaining is washed off, and, in use, the plate carrying the lap is mounted at a slight tilt in a dish and the surface is washed continuously with a slow stream of white spirit to remove loose particles

MECHANICAL POLISHING

Mechanical polishing is often done in two stages, with a coarse and a fine abrasive or polishing agent, respectively The coarse polishing stage is carried out at 300r.p.m., uses a low nap or napless cloth such as Selvyt or synthetic cloth (The nap is intended to retain the abrasive without causing relief effects.) It is fed with a suspension of a relatively coarse abrasive The final polishing stage is carried out with finer abrasive at a lower rotational speed (100 r.p.m.) using medium nap cloth, preferably dense electroflocked terylene fibres bonded to a chemically resistant backing Polishing agents include a-alumina, y-alumina, magnesium oxide, chromium oxide, proprietary metal polishes and diamond dust The polishing agent may have a cutting action or it may produce a 'flowed' layer on the surface or both The modem tendency is to use cutting, rather than flowing, polishing agents, and diamond dust is now preferred r-Alumina (a fastcutting hard material) may be made by roasting aluminium sulphate to 1400°C (a high proportion of a is obtained at 1200°C) and can be used without further treatment y-Alumina suitable for fine polishing may be made by heating to 950°C Suitable magnesium oxide is obtainable cheaply from

medical suppliers Magnesium oxide is slowly converted to carbonate when damp, so polishing cloths, if kept overnight, are cleaned with dilute acid and thoroughly washed Diamond powder of

up to 12pm diameter is used for rough polishing and 0-1 or O-ipm diameter for fine polishing

(usually to be followed briefly with y-alumina, as it leaves very fine scratches) The powder may simply be rubbed into cloth which is kept lubricated with white spirit (a plastic rim pressed on to the polishing wheel conserves the powder), or may be made into a cream The recipe below'

10-8 Metallography

The stearic acid is melted and heated to 80-90°C The triethanolamine and most of the water are mixed and heated to the same temperature range, a small amount of wetting agent and the diamond powder are added, and the abrasive is shaken into uniform suspension The molten stearic acid is stirred vigorously with a mechanical stirrer and the abrasive suspension is introduced rapidly The water not used in the original suspension can be used to wash in any abrasive remaining in the container Continue stirring until the emulsion cools and thickens Where it is particularly required to avoid relief effects in specimens containing constituents of widely differing hardness, diamond dust may be used on a pile-free nylon or terylene cloth Some metals are readily stained or corroded in the presence of water, and for these a non- aqueous polishing mixture, normally diamond with white spirit, is preferred In borderline cases the use of distilled water, rather than tap water, helps to avoid staining

After polishing by any method, the specimen must be thoroughly washed and dried as described under Etching (p 10-16), or washed and etched immediately The specimen should be flooded with

water, then with alcohol or acetone to remove all water and finally dried with a blast of hot air If

the polish or etch is non-aqueous, wash with alcohol or acetone

Polish attack is a method of hastening polishing by the simultaneous use of an etching agent

For instance, ammonia is used with advantage on the pad in polishing copper alloys The action is thought to depend on the enhanced chemical activity of the 'flowed' layer

Attack polishing in a deep layer of liquid is done by mounting a polythene pot on the spindle of

the polishing machine, with the polishing pad in it and submerged in the liquid: Table 10.3

gives reagents for use with various metals by this method Several solutions have also been proposed for magnesium alloys.'

Uranium Cr03 5Og 20-30 Medium contrast under polarized light, no pitting, good

HZO loom1 resistance to oxidation

HNO, (1.40) lOml

Glycerol 150ml

Glycerol 150 ml than usual

Zirconium HNO, (1.40) 50ml 1-10 Good contrast under polarized light Slight grain relief

Bismuth HNO, (1.40) 5Oml 3-5 Good contrast under polarized light Requires less pressure Chromium (COOH), 15g 5-10 Bright polish revealing oxides, etc

a nearly flat (Le constant current) region in the curve for cell current versus voltage As the voltage

is increased (see Figure lO.l), etching (AB) is replaced by film formation (BC) The voltage then increases and the current falls slightly as the film disappears and polishing conditions are established (CD) At higher voltages, gas evolution occurs with pitting Near E gas evolution is

rapid and polishing continues but the region just below D is preferred By reducing the voltage to

Microscopic examination 10-9

Figure la1 Idealized relationship between current density and voltage in electropolishing cell

below B, the specimen can be etched in the same operation For many specimens electropolishing leads to a great saving in time, and it reliably produces surfaces free from strain provided sufficient metal is removed in the process It tends to exaggerate porosity and is unsuitable for highly porous specimens Inclusions are often removed, though not invariably, and their place taken by severe pits Many two-phase and complex alloys, however, can be successfully polished

Apparatus To cover the widest range of applications a d.c supply of 4-5 A at voltages variable

up to at least 60 V is required, but some solutions require only 2 V Accurate voltage regulation is essential, and a rectifier set fed from a varix, a tapped battery or a potentiometer circuit across a constant d.c source is recommended Published recommendations for particular solutions sometimes state the voltage, and sometimes the current density, required It is preferable to work

on voltage, as the current density for a given electrode condition is much affected by temperature and other variables If both are stated, but cannot be simultaneously obtained, the solution is probably wrong; if it is not, the current density should be disregarded Two general cell arrang- ments are used: with electrodes in a beaker of still or gently stirred solution, and with flowing or pumped electr~lyte."-'~ The first arrangement is easily set up and often suffices; the second is more powerful but requires more complicated apparatus (obtainable commercially, however) The characteristics are quite different: with flowing electrolyte a good polish may be obtained with more strongly conducting solutions, and hence with higher current densities, and it is therefore frequently possible to remove more metal in polishing and to start with a more roughly prepared

surface A small area of an article may be electropolished by the use of electrolyte flowing from a vertical jet above the article, the jet itself containing a projecting wire to act as cathode.I3 In suitable conditions, polishing of an area already rubbed with emery may be completed in 3-10s

Apparatus for this method is also available commercially

Jacquet has described a device (the 'Ellapol') in which an electrolyte is applied'to the surface by

a small swab surrounding the cathode The device can conveniently be used to polish a small area

of a large component in situ (see e.g., refs 14-16)

Solutions for electropolishing particular metals are listed in Table 10.4 Table 10.4 is not a

complete list, but should cover most requirements More detailed solutions are given in refs 1, 2, 8

and 9 Minor differences between solutions are often a consequence of the cell used The most

widely useful solutions are methyl alcohol-nitric acid mixtures, strong solutions of phosphoric acid and mixtures of perchloric acid with alcohol, acetic acid or acetic anhydride Mixtures of perchloric acid with acetic anhydride, although frequently the best polishing agents, are often explosive and deserve respect They must be kept cold in use; plastics (especially cellulose) and bismuth must be kept away from them, and they must not be stored in the laboratory as they are liable to explode without apparent reason The explosion of a few hundred millilitres is not likely

10-10 Metallography

Perchloric acid

acetic acid anhydride Figure 10.2 ChnraeteristicsofgercWoricoc~J~~ieMhydr~e/watersohuions(gfterJacquet8, "andPetzow')

=Typical electrolytes

to do great physical damage, but larger quantities should not be used The limits of the dangerous

mixtures, according to Jacquet, the originator,' '' are indicated in Figure 10.2 Perchloric acid must always be added to the acetic anhydride-water mixture to avoid compositions in the detonation zone

Table 10.4 ELECTROLYTIC POLISHING SOLUTIONS FOR VARIOUS METALS A N D ALLOYS

Because of the considerable number of solutions published in the literature, a selection has been made

on the basis of (a) wide usage, (b) simplicity of composition, and (c) least danger References 1 and 2

provide a wider range of compositions Temperatures should be in the range 15-35°C Cooling should be

used to avoid temperatures above 35°C unless stated otherwise

up to 2min

15-60s

15-60s 15-60s 15-60s 15-60s

15-60s 15-60s

Cathode

Stainless steel Stainless steel Stainless steel Stainless steel Nickel Stainless steel Stainless steel Stainless steel Stainless steel

Stainless steel Stainless steel

Microscopic examination 10-11 Table 10.qa) ELFCTROLYTIC POLlSHING SOLUTIONS FOR VARIOUS MmALS Ah9 ALLOYS. eontinued

Ni, Sn, Ag, Be

Ti, Zr, U, Pb Complex steels and nickel alloy general

AI alloys including AI-Si alloys Fe-Si alloys Sb Preferred solution for A1 alloys

Germanium and silicon Titanium

Vanadium Zirconium

Cr, Ti, U, Zr, Fe Cast iron, aU steels, v

Re and many other metals

Ti, Zr, U steels Superalloys

Stainless steel

590 ml

6 mi 350ml

1C-60 up to 2min Stainless steel

800ml 200ml

U, Ti, Zr, AI steels Superalloys

40-100 up to 15min Stainless steel

700 ml 300ml

Nickel, Pb, especially P b S b alloys

Cobalt, F e S i alloys

Cu, Cu alloys (not Cu-

Sn) Stainless steels-

40400 up to Smin Stainless steel 1-2 up to 5min

1-1.6 I M m h

Stainless steel copper

at 40°C

U (preferred solution)

1.56.0 up to lOmin

1.5-6.0 lmin 6-18 lmin

Keep below 27°C

Stainless steel Stainless steel

Stainless steel

875 ml 125ml

(Wanting: This solution

will decompose vigorous

if kept, especially if

cathode left in it Throw

away solution as soon

at finished with)

Hydrochloric acid (1.19)

Sulphuric acid (1.84)

Keep cool below 2°C

Avoid water contamina-

685 ml

225 ml

90 ml

885ml IOOml

Tin Tin bronzes (low 2 up to 15min Copper tin ~ 6 % )

(use at -40°C) Bismuth

25-50 5min Stainless steel

20-40 up to 3min Stainless steel 9-12 up to lOmin Stainless steel

7-5 2-4min Graphite

Microscopic examination 10-13 Table laqr) ELECTROLYTIC POLISHING SOLbTONS FOR VARIOUS METALS AND ALLOYS-mntinued

Cell

34 Sodium hydroxide lOOg Tungsten lead 6 10 min Graphite

35 Methanol 600 ml

Distilled water to 1 OOO ml

Nitric acid (1.40)

Cu-Zn, Ni-Cr Warning: Do not keep Stainless steel, In, Co

longer than necessary Very versatile

May become explosive

On no amount substitute

ethanol for methanol

330ml Ni, Cu, Zn, Ni-Cu 40-70 10-60s Stainless steel

Table 10A(b) RECOMMENDED ELECTROPOLISHING SOLUTION FROM TABLE l0.qa) FOR SPECIFIC METALS AND ALLOYS

10-14 Metallography

work-free surface by other means, as with some very soft metals or where other difficulties

are encountered, it may provide the best method of preliminary or final preparation

In general, a ground or turned specimen is held in the polishing agent until a polish is obtained, and it is then etched or washed and dried, as appropriate Reagents are listed in Table 10.5

Table 10.5 REAGENTS FOR CHEMICAL

Tem- perature Time "C Remarks

Hydrochloric acid lOml

Orthouhosuhoric acid lOml

30 s- 85 Very useful for studying alloys

2 min containing intermetallic compound&

Several 49-50 Rate of metal removal is approx min

e.g AI-Cu, AI-Fe and AI-Si alloys

1 pm min-' Passive film formed

may be removed by immersion for 15-30 s in 10% sulphuric acid

5-10s 20 Cycles of dipping for a few seconds,

followed immediately by washing in

a rapid stream of water are used until a bright surface is obtained

absent 1-2 min 60-70 Finish is better when copper oxide is

1-2 min 70-80 Specimen should be agitated

5 s 40 Use periods of 5 s immersion followed

immediately by washing in a rapid stream of water Slight variations in cornpasition are needed for a-p

and fi-y brasses to prevent differential attack With p-y alloys,

a dull film forms and this can be

removed by immersion in a saturated solution of chromic acid

in fuming nitric acid for a few seconds followed by washing

5-10s 20 -

3-4 drops 45ml 5-10s 20 As for zirconium

Oxalicacid (1OOgl-l) 28ml before use Careful washing is Hydrogen peroxide necessary before treatment A

(30%) 4 ml microstructure is pbtained similar to

that produced by mechanical polishing, followed by etching with Nital

*Acids are wncentratcd, unkpg otherwise indiicd

Microscopic emmination 10-15 Table 10.5 REAGENTS FOR CHEMICAL POLISHMG-continued

Lead Hydrogen peroxide Periods 20 Use Russell's reagent (Table 10.1) to

(30% 80ml of check that any flowed layer has Glacial acetic acid 80ml 5-10s been removed before final polishing

in this reagent Magnesium Fuming nitric acid 75 ,-I Periods 20 The reaction reaches almost explosive

Water 25ml o f 3 s violence after about a minute, but if

allowed to continue it ceases after several minutes, leaving a polished

surface ready for eaamination

Specimen should be washed immediately after removal from solution

Nitric acid (1.40) 30ml t-lmin 85-95 This solution gives a very good polish

Sulphuric acid (1.84) lOml

Orthophosphoric acid

Glacial acetic acid Mml

Nitric acid (1.40) 20ml 5-10s 20 1:l mixture also used

(1.40) 40-45 ml repeated interface, and specimen is therefore

held near surface of liquid Hydrogen Water

Hydrofluoric acid peroxide(30%)canbeused in placeof