NGHIEN CU'U- iKAUyOI NGHIEN CI>U XAC DINH CAC THAM S 6 CONG NGHE GIA CONG CO NHIET T 6 | UU HOP KIM Cu-Ni-Si STUDY ON DETERMINING OPTIMAL THERMOMECHANICAL PROCESS PARAMETERS OF Cu-Ni-
Trang 1NGHIEN CU'U- iKAUyOI
NGHIEN CI>U XAC DINH CAC THAM S 6 CONG NGHE
GIA CONG CO NHIET T 6 | UU HOP KIM Cu-Ni-Si
STUDY ON DETERMINING OPTIMAL THERMOMECHANICAL PROCESS
PARAMETERS OF Cu-Ni-Si ALLOY
Philng liiin Anh, Phairo B^i Phird-c
Khoa Ca khi, Hgc vien Ky thuat Q u ^ su, Bd Qudc phdng
TOM TAX
Bdi bdo ndy trinh bdy kit qud nghiin cuu dnh hudng cua cdc tham sd qua trinh ca nhiet den
dg cung vd do ddn dien cua hgp kim BCuNiSSi Thdng qua quy hogch thuc nghiem true giao cdp 2
v&i cdc tham sd cdng nghe thay ddi gdm, muc dd biin dgng ngudi truac trong khodng (30-70) %,
nhiet do hda gid trong khodng (425-525) °C vd then gian hda gid trong khodng (3,5-8,5) h, nhdm tdc
gid da xdy dung dugc cdc hdm m^c tiiu, bieu dien suphu thugc cda dd cung, do dan diin vdo muc
do bien dgng ngudi truac, thai gian, nhiet dg hda gid dip theo vd xdc dinh cdc thdng sd cdng nghe
tdi uu khi gia cdng hgp kim BCuNi3Si Thuc nghiem chi ra rang, sai sd cua cdc so lieu thtrc nghiem
so vai tinh todn khdng vugt qud 5 %
Tu khda: Hgp Mm BCuNiSSi, gia cdng canhiet, bien dang ngudi, hda gid, dd cung dg ddn diin
ABSTRACT
In this paper, effect of thermomechanical process parameters on hardness and electrical
conductivity ofCuNi3Si alloy was studied Through the Orthogonal Experimental Desi^ (OED)
method with cold pre-deformation degree of (30-70) %, aging temperature of (425-525) "C and
aging time of (3.5-8.5) h, the authors built objective functions, that represented the dependence of
hardness and electrical conductivity on cold pre-deformation degree, aging time and temperature,
and determined the optimal technological parameters for fabrication ofCuNiSSi alloy Variations
of the experimental results with theoretical calculations does not exceed 5 %
Keywords: CuNiSSi alloy, thermomechanical treatment, cold deformation, aging, hardness,
electrical conductivity <B
ISSN 0866 - 7056
Trang 2NGHIEN CO'U-TRAODOI
l.D^TVANDE
Hgp kim Cu-Ni-Si dugc ung dung rdng
rai trong ehd t^o mdy cung nhu trong ky thudt
didn do dap iing dugc yeu cau cao cd vd do ben
va dd ddn didu [1,2] Thdi gian gdn day, cd rit
nhidu cdng trinh nghien cuu ve hgp kim
Cu-Ni-Si nhdm mgc dich ldm tang do ben, tang do
ddn dien hoac ket hgp tang ddng thdi do ben
va do dM dien Cae phuang phdp cdng nghe
dd dat dugc ddng thdi hai muc tieu nay kha
nhiiu va mdt trong eac phuang phap dan gidn
va hieu qua la su dung edng nghe ca nhiet hgp
kun Cu-Ni-Si, kdt hgp cdng nghd nhidt luyen
thdng thudng bao gdm, tdi va hda gid xen ke
dd Id nguydn cdng bidn dang ngudi [3-5] Quy
trinh cdng nghe ca nhiet dien hinh duge chi ra
trdn hinh 1
2 NQI DUNG NGHIEN ClTU
i H O « ^
V A A A / X
Hinh 1 Sa do cdng ngh? ca nhiet hgp kim
BCuNiSSi
Dua tren ea sd eac ket qua tiiu dugc khi khdo sat dnh huong cua nhidt do, thdi gian tdi ddn tinh chat hgp kim Cu-Ni-Si cua cdc nghi8n ciiu trude, bai bao tap trung vao nghien eihi dnh hudng eua miie do bien dang ngudi, nhiet
dd va thdi gian hda gia ddn do ciing va dd ddn dien ciia hgp kim Cu-Ni-Si, sii dung phuang phdp quy hoach thuc nghiem de tim ra eac tham sd tdi uu
Hgp kim BCuNiSSi ed tiianh phdn hda hgc duge eho trong bang 1
Bdng 1 Thdnh phdn hda hgc hgp kim BCuNiSSi nghiin cuu
Zn
0,0095
Pb
0,0026
Sn 1 Fe
0,0033 1 0,050
Ni 3,07
Si 1,00
Cr 0,0007
AI 0,0033
Ti 0,0014
Cu 95,8 Cac tfan m l u ph5ng BCuNiSSi co kich
thu6c 60x5x2 mm (dai x rang x day) tmac tien
dugc nung va toi trong nuoc Si chuin bi tiSn
hanh cac nghiSn cuu tiSp theo Thuc nghiSm
cho thiy, d6i voi hpp kim BCuNiSSi, nhiSt do
toi t6t nhat nen chon la 850 °C [6-8]
Tien hanh xay dung ma tran quy hoach
thuc nghiem va thuc hien cac thi nghiem bidn
dang nguoi ngay sau toi va h6a gia nhta tao
tiep theo voi 3 tham s6 cong nghe thay d6i co
ban: Miic do biSn dang (e), nhiet do (T) va thai
gian hoa gia (t) Cac tinh chit cila hap kim cin
xac djnh sau gia cong co nhiet la do Cling (HV5)
dugc do tren may do dO cling Vickers Wilson Wolpert (Trung Quoc) va do din dien (%IACS) dugc xdc dinh thong qua dien trg R cua miu dugc do tren thilt bi do dien tro Megger Digital Microhmmeter DLRO-10 (Anh)
3 KET QUA NGHIEN CUtI VA THAO LUAN
Tu tinh chat cua hgp kim CuNi3Si va dac diem cong nghe gia cong eg nhift, tam thi
nghiSm dugc xac dinh 6 miic dp hiin dang £
= 50 %; nhiSt do hoa gia T = 475 °C; thoi gian hoa gia t ^ 6 h
ISSN 0866 • 7056 TAP CHI CO KHl VIET NAM, S3 1+2 nam 2017
Trang 3NGHieN CLfU - TRAO DOI
Khoang biSn thien trong thi nghiem ca
|la: Ae=20 %; AT=50°C; At=2,5 h
Muc trdn trong ihi nghiem ca ban la:
s - 7 0 % ; T = 525'C;t=8,5h
Miic dudi trong thi nghidm ea ban la:
e ? 30 %; T = 425 "C; t = 3,5 h
De tim cue tri eiia hdm hdi quy, trudc het
phai dung md hinh todn hgc cd dang da thiic
bdc 2, nhu vay, ta se xdy dung quy hoach thuc
nghiem trgc giao bdc 2 du vdri 15 thi nghiem,
trong do 8 thi nghiem ea ban, 1 thi nghiem d
tam va 6 thi nghiem trong khdng gian md rdng
Khoang bien thien cua cdc bidn trong
khdng gian md rdng dugc xac dinh:
Vdi mirc do bien dang:
Q).As = 1,215 X 20 = 24,3 %, quy ti-dn
bdng 24%
Vdi nhiet do hda gia:
co.AT = 1,215 X 50 = 60,75 °C, quy ti-dn
bdng 60 °C
(D.At =1,215 X 2,5 = 3,04 h vd quy ti-dn bang 3 h
Trong 15 thi nghiem tiieo quy hoach thuc nghiem true giao cap 2, gia tri ciia eac bidn trong
ma trdn thge nghiem dugc xdy dung nhu sau:
Miie do bidn dang:
e (%) = {26; 30; 50; 70; 74} dugc ma
h o a b d i Xj;
Nhiet do hda gia: T ("C) = (415; 425; 475; 525; 535} dugc ma hda bdi x2;
Thdi gian hda gia: t (h) = {3; 3,5; 6; 8,5; 9} duge ma hda bdi x^
Cae ham mue tidu y^, y^ Idn lugt la do
cung va do din dien ed dang:
Trong dd: b,,, b., b^^ b la eae he sd cua ham hdi quy
Ma trdn thuc nghiem dugc xdy dung nhu Vol thai gian hda gia: trong bang 2
Bdng 2 Ma trgn thuc nghiem:
N,
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
\
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
Xj
+
+
+
+
-0
•HS
-ffi
0
0
0
0
^
+
+
-+
f
0
0
0
+10
-to
0
0
^
-+ + + +
-0
0
0
0
0 -Ho -co
l A
+
-+ +
0
0
0
0
0
0
0
I,f,
- -1 f
-+ +
0
0
0
0
0
0
0
v
+
f
-+ +
-0
0
0
0
0
0
0
A
0,27 0,27 0,27 0,27 0,27 0,27 0,27 0,27 -0,73 0,75 0,75 -0,73 -0,73 -0,73 -0,73
A 0,27 0,27 0;27 0,27 0,27 0,27 0,27 0,27 -0,73 -0,73 -0,73 0,75 0,75 -0,73 -0,73
A 0,27 0,27 0,27 0,27 0,27 0,27 0,27 0,27 -0,73 -0,73 -0,73 -0,73 -0,73 0,75 0,75
Y, X,
ISSN 0866-7056 TAP CHl CO KHl VIET NAM, 85 1+2 r 12017
Trang 4NGHIEN CCrU-TRAO D 6 |
Tidn hanh thgc nghidm theo ma tran quy hoach, xac dinh dugc do eiing va do dan dien cua hgp kim BCuNi3Si nhu trong bang 3
Bdng 3 Ket qud thifc nghiim theo ma trgn thifc nghiim:
TT
1
2
3
4
5
6
7
8
9
10
11
12
13
14-15
E, %
70
70
70
70
30
30
30
30
50
74
26
50
• 50
50
50
%'C
425
525
425
525
425
525
425
525
475
475
475
535
415
475
475
t , h 3,5 3,5 8,5 8,5 8,5 8,5 3,5 3,5 6,0 6,0 6,0 6,0 6,0 9,0 3,0
DScihlgHVS 274,3 196,8 239,5 184,8 185,6 148,3 241,9 185,8 224,5 217,0 222,0 178,6 250,0 187,5 253,6
9 8 d i n ai$n,%IACS 35,7 38,7 37,8 36,1 36,4 35,3 33,6 38,2 39,1 42,4 39,1 38,3 36,0 39,0 36,8 Sau khi kiSm tra tinh co nghia cua cac he so va tinh tugng thich eia ham h6i quy, phucmg trinh h6i quy do ciing (y,) va do din diSn (y^) co dang:
J, =226.92 + 10.32X, -25.24:cj -\l.Ux, -l.Wxl
y^ = 3 9 9 8 + 0.7U, -1.02xjX3 -\.f,(,x\-\.2(,y^
(2) (3)
Sit dung cac c6ng cu toan hgc dS tim cue tri cila phuomg trinh h3i quy (2), (3), gi4 tri Ign nhit cua do cung va dp dan dien dugc xac dinh nhu trong bang 4
Bdng 4 Ket qud xdc dinh cue tri ciia phuang trinh hSi quy:
Ham muc tieu | M f c d$ bi^n dang
Ham
y,
y
Cue tri
273,21
40,69
Gia tri ma Iioa
1
1
Gia tri tllllC
7 0 %
7 0 %
Nliift dQ lioa gii Gia tri ma hoa -1
0
Gia trj tliu-c
425 "C
475 "C
Thoi gian hoa gia Gid tr} ma hoa -1
0
Gii trj thuc 3,5 h
6 h
ISSN 0866 - 7056 TAP CHi CO KHI V I £ T NAM, Sd 1+2 nam 2017
Trang 5NGHIEN CO'U-TRAOeoi
Tii p h u a n g trinh h^i quy xdc dinh dugc
cd thd bidu didn mdi quan hd ciia ham mgc tidu
tiieo cac bien khi cd dinh bidn cdn I^i dd t h i y
rd han su anh hudng cua miic do bien dang,
nhiet do va tiidi gian hda gia den dg eung vd do
dan di$n cua hgp kim BCuNi3Si, cu thd nhu
trSn cdc hinh 3 vd 4
Thdng qua phucmg trinh hdi quy va dd
thi tren cdc hinh 3, de dang nhdn thdy khi tang
mu:c dg bidn dang trong khodng (30-70) % thi
dg cumg hgp kim BCuNi3Si tang Cdn khi tang
tiidi gian hda gid trong khoang (3,5-8,5) h thi
dp cung hgp kim BCuNi3Si giam Dd ciing
hgp kimBCuNi3Si dat cue dai la 273.21 HV5
khi s = 70 %, T = 425 »C; t - 3,5 h
Hinh 3 Suphu thugc cda do cieng vdo thai gian
hoa gid khi muc do biin dgng bang 70 %
Hinh 4 Suphg thudc cua do ddn diin vdo th&i
gian hda gid khi muc do bien dgng bdng 70 %
Tuang tu, de dang nhan thdy khi tang
muc do bidn dang ti-ong khodng (30-70) %
thi dd d i n didn hgp kim BCuNi3Si tang
Dong thdii, khi tang nhiet do hda gia trong khoang (425-475) °C thi do ddn dien hgp kim BCiiNi3Si tMig, tidp tuc tang nhiet dd hda gia trong khodng (475-525) "C tiii do d i n dien hgp kim BCuNi3Si lai gidm Cdn khi tang thdi gian hda gia trong khodng (3,5-6) h thi do ddn dien hgp kun BCuNi3Si ^ n g , tidp tuc tang tiidi gian hda gid trong khodng (6-8,5) h tiii do ddn dien hgp kim BCiiNi3Si lai gidm Dd dan didn hgp kim BCuNi3Si dat ege dai Id 40,69
%IACS khi e = 70 %, T = 475 °C va t = 6 h
Qua trinh thuc nghiem kiem chiing 3 mdu
da eho ket qua do ciing cua hgp kim BCuNiSSi
dat gia tii cgc dai la 274.3 HV5 (sai sd 0,4 % ) ,
dd dan dien dat gia tri cue dai 42,4 %IACS (sai
sd 4 %) vdi eung chd dd xur If ca nhidt tuang
ling Qua dd cd thd khdng dinh tinh diing dan eua phuang phdp nghidn cim, ket qud dat dugc day tridn vgng trong vide xdc dinh ehe dg gia edng nham xac dinh dnh hudng ciia cac tham
sd edng nghe co nhiet va xdc dinh eac gia tri tdi uu nham ket hgp do ciing va do dan didn cao cho hgp kim BCuNi3Si
4 K E T L U ^ Trong midn gidi ban thuc nghiem ciia eac tham sd gja cdng co nhiet, su dnh hudng ^lia miic do bien dang, nhidt dd va thai gian hda gia den tinh chat hgp kim BCuNi3Si la dang
ke Khi thuc hidn che do gia edng e a nhiet vdi
e = 70 %, T = 425 °C; t = 3,5 h, do ciing hgp kim BCuNi3Si dat cue dai la 273,21 HV5 Khi thue hidn che dg gia cdng ca nhiet vdi e = 70
%, T - 475 °C; t - 6 h tiii do ddn dien hgp kun BCuNi3Si dat cue dai la 40,69 %IACS Cae sai sd thuc nghiem so vdi tinh toan ndm trong gidi han cho phep (khdng vugt qud 5 % ) K^t qua ndy cd tiid tham khdo khi gia cdng eh^ tao BCuNi3Si d nude ta nhdm muc dieh lam tang
dd ben, tang do ddn dien hodc kdt hgp ddng thdi do bdn va dd ddn dien du cao tiiy theo muc
dich sii dung • ^
ISSN 0866-7056
Trang 6Ngay nhdn bdi: 10/01/2017
Ngdy phan bidn: 15/02/2017
Tai lidu tham khao:
11] Nguyen Khac Xuong; Kim logi vd hgp kim mdu, NXB Khoa hgc Ky thu^t, 2003
[2] CorsonM G; Electrical conductor alloys [JJ Electrical World, 1927 (89), pp 137-139 [3], S Nestorovic; Influence of deformation degree at cold-rolling on the anneal hardening effect in
sintered copper-based alloys (J) Joumal of Mining and Metallurgy, 40B (1) (2004), pp 101-109
[4] S Suzuki, N Shibutani, et al Improvement in strength and electrical conductivity of Cu-Ni-Si glloys
by gging and cold rolling (J) Joumal of Alloys and Compounds, 417 (2006), pp 116-120
[5] Lei Qian, Li Zhou, et al Dynamics of phase transformation of Cu-Ni-Si alloy with super-high strength
and high conductivity during aging (J) Transactions of Nonferrous Metals Society of China, Volume
20 (6), 2010, pp 1006-1011
[6] Lu De-ping, at Al; Calculation of Cu-rich part of Cu-Ni-Si phase diagram (J) Transactions of
Nonferrous Metals Society of China, 17 (2007), pp 12-15
[7] Nguyen Van Duong, Nguyin Nhat Huy, Phiing Tudn Anh; Nghiin cuu che tgo hgp kim dong diin cifc
BCuNi3Si(J) Tap chi Khoa hpc vaKy thu|t, Hgc vidn Ky thu^t Qudn sg, s6 154(4-2013), M 40-44
[8] Phung Tuan Anh, Ld Minh E)uc; Anh hu&ng kit hgp cua biin dgng nguoi vd hoa gid nhdn tgo den do
cimg vd tinh ddn diin ciia hgp kim-dongCu-2,8Ni-l, OSi (J), Tap chi Khoa hpc va Ky thuat, Hpc vien
Ky thudt Quan su, sd 177 (7-2016), tr 123-129
[9] Nguyen Minh Tuy8n; Quy hogch thifc nghiim, Tnidng D^i hgc Bach Khoa TP H6 Chi Mmh, 2005
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