Dd thi nghiem ep ndng dd dd xuat phuang an thiet ke khudn ep ndng bdng graphit nhu sau: Bp khudn graphit dd ep ndng bdt thep hap kim hda thap tao phdi d dang hinh tru cd dudng kinh ngodi
Trang 1N G H I € N cufu ANH HUdNG CUA BI^N DANG T<3l TINH C H A T V A T L I $ U
BANH RANG LUYfiN KIM B O T TRONG TRUYDN D O N G XICH XG MAY
A STUDY ON THE INFLUENCE OF DEFORMATION
ON MATERIAL PROPERTIES OF MOTORBIKE CHAIN SPROCKETS
MADE FROM POWDER LOW-ALLOY STEEL
Ha Minh Hiing, Do Dinh Liromg Vidn Nghidn ciiu Co khi - Bp Cdng Thuong
TOMTAT
Bdi bdo di cdp din su dnh hudng cua muc dd biin dgng vdt ligu bdt thep hop kim hda thdp nhgn dugc sau khi ep ndng sa bd ldn 1, din do xop vd mat do tuang ling ciia nd, nhdm ndng cao ca ly tinh tren mdu bdnh rdng xich chi thu Biin dgng tgo hinh chi tiet bdnh rdng xich truyen dgng xe m^ HONDA cd thi duac thuc hiin bdng phuang phdp ep, hogc dgp a trgng thdi ndng ldn 2 trong khuon kim logi, nhdm tgo ra ling sudt nen nhiiu chiiu vd ddm bdo vdt lieu dgt dugc mat do cudi ciing gdn nhu kim logi ddc xit
ABSTRACT
In this paper, the influence of deformation levels of powder low-alloy steel obtained from preliminary thermal distortion on its porosity and the corresponding density is studied to enhance physico-mechanical properties of trial chain sprockets The results show that, it is possible to pressure form chain sprockets for HONDA motorbikes by secondary hotpressing or forging in metal dies The method was used in order to induce multi-direction compressive stresses inside, and to ensure that the last level of material density is almost the same as that of solid metals
L B A T V A N D E yo= 39,23 + 26,66 %, cdn mdt dp hrong img li
pp = 4,77 -^5,75 g/cm^ Trpng khi dd yeu can ve Nhu da de cap trpng cdc cdng trinh nghien mat dd vdt lipu trdn san phdm banh rang xich theo ciiu thuc nghiem vd dnh hudng cua chd dp dp thidu mdu ciia Nhdt Ban cdn dat gid tri khdng nhd hon kdt ridng bidt [1], cimg nhu hai qua trinh dd dupe p^^ = 7,82 g/cm' [2]
thuc hidn ddng thdi (thieu kdt dudi dp luc) [2], [3]
ddi vdi bpt thep hpp kim hda thdp ldm bdnh rang Vdi ydu edu tmh chdt cua vdt lieu nhu vdy, ddn CO ly tinh cua vat heu luypn kim bdt cho thiy: ro rang la khdng thd sii dung vat lieu bdt thep hpp
Dp xdp va mat dp sau thieu kdt vd sau ep ndng so kim hoa thdp d trang thai nhjn dupe ngay sau khi
bp lan 1 cdn tuong ddi cao Dp xdp thd tich trung ep ndng so bp ldn 1 trong khudn graphit, ma phii binh, xdc dinh bang phuong phap can thuy tinh d qua bidn dang ddo dd ndng cao co ly tmh ciia n6
cdng hiiih, doi vdi cdc mlu bdt thep nghidn trdn Dd Idm rd vdn dd ndy, bdi bdo ndy dd cap A til bpt sdt HOGANAS vd Cr, Ni, W trong midn kdt qua thuc nghidm bidn d ^ g deo ldn 2, ttong
quy hp?ich thuc nghidm da chpn dat ttong khoang khudn kim loai cd prophin dinh hinh vdnh rdng
Trang 2ngoai va Id rang then cua banh rdng xich
HD-GF6, d trang thdi ndng ddi vdi vdt lieu bdt thep
hgp kim hda thdp nhgn duae sau khi ep ndng so
b p l ^ l
2 PHlTOfNG PHAP THI NGHIEM
Nhdm nghien cuu dd tidn hanh chd
tao thir nghiem mdt sd bdnh rang xich xe may
HONDA (Idy ky hidu la HD-GF6) bdng phuorng
phap luydn kim bOt Dd thi nghiem ep ndng dd
dd xuat phuang an thiet ke khudn ep ndng bdng
graphit nhu sau: Bp khudn graphit dd ep ndng
bdt thep hap kim hda thap tao phdi d dang hinh
tru cd dudng kinh ngodi bdng dudng kinh dinh
rang, cdn dudng kinh Id bdn trong bdng dudng
kinh chdn rang then ciia bdnh rang xich edn ehd
tao (hinh 1 a);
- Nhu vay, bd khudn ep ndng gdm: 01 cdi ep; 01 chdy ep trdn ed dudng kinh nhd han dudng kinh Id khudn ep khoang 0,2 nun vd 01 chdy ep dudi cd dang bdc vdi dudng kinh than chdy bdng dudng kinh Id phdi ep nhdm tao iS ngay trong qud trinh ep ndng sa bd lan 1 Kich thudc eiia khudn
va chdy ep dugc tinh todn vdi lupng du cho bidn dang deo sau thieu kdt d miic edn thiet (hinh 1 b);
- Cdc budc nghien trpn tao hot thdp hpp kim thdp, quy trinh ep ndng sa bd ldn 1 thuc hi$n nhu da hinh bay trong bdi bdo [3] Sau dd sir dung khudn dp ndng tinh chinh ldn 2 bang kim logi vdi thidt kd tao hinh vanh rdng ngodi va Id rang then bdn trong eua ehi tidt banh rdng xich HD-GF6 can ehd thd (hinh 2) Phdi bdnh rdng xich sau ep ndng ldn 1 duge cho vdo hop kin phu bdt graphit trpn 1^ bdt A1203 rdi nung ndng trong Id dien trd thi nghi$m den nhidt do ep ndng lan 2 (T^^)
b) c) Hinh 2 Anh chup bq khuon ep (dgp) nong phdi bdnh rdng xich HD-GF6 tie bgt thep hgp kim hoa thdp:
a) Coi ep; b) Chdy ep tren vd dudi; c) Ty ep tgo Id rdng then cua bdnh rdng xich
3 KET QUA THI NGHIEM VA BAN LUAN
3.1 Ep nong so* b$ l4n 1:
Cdc phdi banh rang xich (PBR) nhdn
dugc sau ep ndng so bd lan 1 tir bpt thep hpp
kim hda thdp d mpt sd ehe dp cho trudc: p^^ =
10 - 30 MPa; T^„ = 1200 - 1300«C; t^_, = 2,0
-^ 3,0 phut Cdc mau thi nghi$m da dupe gidm dinh de tinh todn dp xdp thd tich trung binh
t^en' °^)> ^^^ ^d tuang ling (p^^, g/em^) vd dp
cung tdi trpng nhd (HV, MPa) d trang thdi ngay sau khi ep ndng sa bd ldn 1, kdt qud thi nghi$m cho trong bdng 1
Bdng 1 Ca ly tinh cua phdi bdnh rdng xich HD~GF6 sau ep nong sa bd ldn 1
Ky hipu
man
PBRl
PBR 2
PBR 3
Ddxdp
TB,y^_,%
35,2533
32,8666
32,7833
Mat dd, p^_^,g/cm'
5,08261 5,26997 5,27651
Dp Cling HV,MPa 1349+1510 1487+1686 1638-1880
Ky hieu mau PBR 4 PBR 5
Dp xdp TB,Y,,,%
30,8333 27,6666
Mat dp, p^_^,g/cm^
5,42961 5,67816
Dp Cling, HV,MPa 1735+1875 1874+2004
Chieu ddy sau ep ndng ldn 2: 8,4 ^8,5 mm Chidd ep ndng ldn 1: T = 1250 + ]300°C: (,.= 2,5 + 3,0phiit;p_= 10 * 30 MPa
TAP CHl CO KHl VI$T NAM V Sd 10 (Thdng 10 nim 2012)
Trang 3+ 2004 MPa Vat lieu nay cdn phai dupe tidp tyc bidn dang ndng ttong khudn kim loai da cho 6 hinh 2 dd ldm gidm dp xdp, tang mat dd vd co tinh
NGHIEN cufu - TRAO B 6 I
- Phdn tich cac kdt qua thuc nghiem trong
bdng 1 cho thdy: Vdi chd do dp ndng so bd lan 1
dp xdp thd tich trung binh va mat dp tuong ling
cua cdc phdi banh rang xich dat 6 miic tdt hon so cua no
voi cdc mlu thi nghiem sau ep ndng dinh hudng , , cdng nghe da dd cap ttong cdng ttinh [2] vd cd - Ket qua nghien ciiu khao sat va chup anh gid tri nhu sau: Dd xdp thd tich ttung binh cdn td chiic td vi vat lieu bdt thdp hop k m hoa thap ldn- yo = 35 25 - 27 66 %; Mdt dd tuong ling cdn nhan dupe tten co sd bpt sat HOGANAS he [Fe thdp- po = 5 082 + 5,678 g/cm3; Dd ciing trung - Cu - C-grafit - Zn-Stearat] co nghien ttdn them binh cua cac phdi bdnh rang xich sau dp ndng ldn cac nguydn td nhu Cr, Ni, W va dp ndng so bd ldn
1 phu thudc do xdp, dat ttong khodng: HV =1349 1 dupe cho ttdn hinh 3a-d duoi day ,
c)MduBRX3,xS00 20ftm b) Mdu BRX4, xSOO 20^m Hinh 3 Anh chup to chue te vi vdt lieu a phdn thdn bdnh rdng xich sau ep nong ldn 1, khdo sdt dgc theo hic&ng ep (a; b; c) vd ngang hudng ep (d)
- Phan tich ket qua cho tten hinh 3a (x
500) khao sat dpc hudng ep cho thdy: phdn bd
ciia cdc phdn tii cd man den hinh gan cau va hinh
"qua chiiy" rdt ddng ddu ttong toan bd didn tich
nen vat lieu dupe khdo sdt ciia man bdnh rang
xich (ky hieu BRX 1), cdn cac vung td chiic cd
mdu sang vd mau xam tuong ddi ddng ddu Didu
dd ddm bdo tinh chdt vdt lieu nhdn dupe trdn mdu
thi nghidm ndy kha tdt, tinh di hudng edu tnic cdc
pha hinh thdnh ttong vat lieu banh rang sau ^ ndng tinh chinh lan 2 thdp Ci ddy khdng phat hi?n thdy su cd mat cua nguyen td ddng , cd thd vi do ham lupng thdp (dudi 2 % Cu khdi lupng), oSo
nd da hi hda tan ttong ndn bpt sdt HOGANAS Thanh phan vdt lieu tai cdc tieu viing co hinh "qui chuy" cd the dupe xdc dinh bang phuong phap phdn tich SEM-EDX [2] Ndu so sdnh djc lint edu true kim loai cua vat lieu nhdn dupe tten mau
Trang 4BRX 2 sau ep ndng ldn 2 vdi dp xdp du va mat
dp tuang ling cua nd (bang 2) thi cd thd cho rdng
chat lupng vat lieu duge danh gia theo tieu chi
tdng hpp ca ly tinh vd dac didm edu tnic hat min
vd phdn bd ddng deu la dat yen cau, dam bao
didu kidn lam vide d tdi trpng cd va dap vd chiu
mdi mdn cao
- Phdn tich ket qua cho trdn hinh 3 b va
hinh 3c (x 500), khao sat doc hudng ep cho thay:
phdn bd cua cac phan tu cd mau den hinh gan cau
vd mpt sd it hinh "qua chuy" kha ddng deu trong
todn bd didn tich nen vat lieu dupe khao sat eua
mdu bdnh rang xich (ky hidu BRX 2), cdn cdc
viing td chiic cd mdu sang vd mau xdm tuong
ddi ddng ddu Tinh chat vat lieu nhdn dupe d thi
nghiem nay ciing kha tdt, tinh di hudng cau tnic
eiia eac pha hinh thdnh trong vat lieu mau BRX
2 sau ep ndng tinh chinh lan 2 thdp Tuy nhien,
d ddy ed phat hien thdy mdt vai phdn tir edu tnic
ed man vang sang phan bd cue bd trong ndn bdt
sdt H O G A N A S , cd thd dd la hat Cu chua bi hda
tan Chat lugng vat lieu mdu BRX 2 danh gid
theo tidu chi tdng hgp ca ly tinh vd dae didm cau tnic hat min va phdn bd ddng ddu ciia man thi nghiem nay dat yeu cau, dam bao lam vide tdt trong dieu kien tdi trong cd va dap va chiu mdi mdn cao
- Td chiic te vi vat lieu d mau banh rang xich (ky hieu BRX 4) cho tren hinh 3d cd diem dae biet ridng la cd vung cue bd hinh thanh edu tnic pha mdi trong phan tu mau den De lam ro thanh phan cua nd phai sii dung ky thudt phdn tieh SEM-EDX va dat ket qua cd the tham khdo trogn cdng trinh [2], khdng xet ddn d day
3.2 Ep nong tinh chinh Ian 2
Anh chup cdc banh rang xich HD-GF6 sau khi ep ndng lan 2 d nhiet dp: Te.n2 ^ 950
OC vdi miic dp bien dang dec the tich tinh todn ciia tdng eac Id xdp dat trong khoang: eV
= 26,36-^34,7 % Chidu day eac mau banh rang xich sau ep ndng lan 2 nhan dugc la 8,2 ± 0 , 1
mm Ca ly tinh cho d bang 2
b> Mdu so 4
a) Mdu so 6 b) Mdu so 7 c) Mdu so 8
Hmh 4 Anh chtip mdu bdnh rdng xich HD-GF sau ep nong tinh chinh ldn 2 tit bgt thep hap kim hoa thdp
(a -^ e) vd sau gia cdng tinh (j)
TAP CHi CO KHf VIET NAM • Sd 10 (Thang 10 ndm 2012) Q
Trang 5NGHIEN Cl/U - TRAO D 6 |
Bdng 2 Ca ly tinh cua bdnh rdng xich HD-GF6 sau ep ndng tinh chinh ldn 2
mlu
B R X I
B R X 2
B R X 3
B R X 4
B R X 5
D $ x 6 p
T B , y,.„,%
35,3333
32,8666
32,7833
30,8333
26,6666
B i d n d ^ g
tdng, ev,%
34,7023
32,3626
32,4003
30,5043
26,3656
D$x6p
T B , ydj.,%
0,631 0,504 0,383 0,329 0,301
M $ t d $ ,
7,8000 7,8100 7,8200 7,8242 7,8264
D § Cling H V ,
M P a
2 3 3 0 + 2 3 9 0 2386-r25S0 2485-r2590
2 5 6 0 + 2 6 1 5
2 5 5 5 + 2 6 2 0
Tj-iew giamx^
98,214
9 8 , 4 6 6 98,831
98,933
98,871
T ^ l ? % ttogcung 1 158,2+172,7
151,2+160
1 3 7 , 7 + 1 5 | 139,4+14«
130,7+13^
ChS rfj5 ^ ndng tinh chbih ldn 2: T,„i = 900 r-9S0 °C; ldm ngu^i trong IMng UiL
Hmh thdi be mat cac mdu bdnh rang xich
sau dp ndng tinh chinh ldn 2 chiing td chdt lupng
thieu kdt bdt thep hgp kun hda thdp a day la kha
tdt (hinh 4) Tij sd lieu d bdng 2 cho thdy:
- Dp xdp du trung binh cua vat lieu tten
cac mdu banh rang xich da giam rd ret tir gid tri
trung binh sau dp ndng so bd ldn 1 ban ddu yo =
35,333 + 27,666 %, cdn lai sau dp nong ldn 2 la
72 = 0,631 + 0,301 % tuong ling vdi miic dp bidn
dang tdng thd tich tuong ddi ndi tten;
- Mat dp tuong ling ciia vdt lieu tren cac
mdu bdnh rang xich da tang manh tir gia tti sau dp
ndng so bd ldn 1 ban ddu po = 5,076 + 5,678 g/
cm' len tdi mat dp ttrcmg ling sau ep ndng ldn 2 la
p2 = 7,80 + 7,826 g/cm', tiic hrong duong vat lieu
dac xit cua thep diic cdn ttuydn thdng;
- Dp Cling tai trpng nhd trung binh cua
banh rang xich chd thir d trang thdi ngay sau khi
dp ndng ldn 2 va lam ngudi trong khdng khi dpi ttong khoang HV = 2328,75 + 2615,0 MPa Nhu vay, vat lieu cua cac banh rang xicji HD-GF6 chd thu sau dp ndng tinh chinh ldn 2 di dat miic gdn vdi kim loai dac xit, co tinh da tdng
len ro ret hon so vdi sau dp ndng so bd ldn 1 3.3 Nghien cihi to chirc te vi vdt lif u bdnh rJii| xich HD-GF6 san ep ndng lan 2
Su nang cao tmh chdt vdt lieu bdt thep hpp kim hda thap, nhan duoc tten co sd bpt sil HOGANAS nghidn ttdn them Cr, Ni, W theu kji dudi dp lire ldn 1 vd sau khi dp ndng ldn 2 la thdng qua ket qua nghien ciiu khoa sat vd chup anh ti chiic td vi vat lieu cho trdn hinh 5a+d
a) Mdu BRX 1x500 20fim
b) Mdu BRX 2, xSOO 20fm
TAP CHl CO KHl VIETNAM • Sd 10 (Thdng 10 ndm 20121
Trang 6Hlnh 5 Anh ch\ip to chiec te vi vdt Ueu a phdn thdn rdng tren mdu bdnh rang xich
sau ep nong tinh chinh ldn 2, khdo sdt doc theo hudng ep
- Phdn tich kdt qud cho tren hinh 5a (x
500) khdo sdt dpc hudng ep cud mau banh rdng
xich ed ky hidu BRX 1, nhung vi tri khao sat tai
vimg thdn banh rang, cho thay: td chiic td vi vdt
lieu rdt min, cac viing cau tnic ed mau den cd
dang gdn cau chiem da sd cdn dang phan tii cau
tnic cue bg chieu dai khdng ldn (duge eho Id lo
xdp) ddu cd kich thudc hinh hpe rat nhd va phdn
bd khd ddu trong pha nen Cac vung edu tnic ed
mdu sang trang kich thude khd min va phdn bd
ddng ddu trong toan bd dien tich ndn vat lieu dugc
khdo sat Td chiic td vi vdt lieu trdn mdu BRX 1
sau dp ndng tinh chinh ldn 2 nhan dugc Id rdt tot,
dat miic gan nhu kim loai dde xit va dam bao ydu
sau lam vide d didu kidn ed tdi trpng va dap vd
shin mdi mdn eao cua bdnh rdng xich truyen ddng
xe may
- Phan tich ket qua cho tren hinh 5b (x
j'OO) khdo sat dpc hudng ep cud mdu bdnh rang
:ich ed ky hidu BRX 2 d phdn than banh rang
,:ho thdy: td chdc td vi vat lieu khdo sat tai vung
han bdnh rang tuang t\r nhu ddi vdi mau BRX 1
ldi trdn Tuy nhidn, kich thudc cac hat cau tnic
d ldn han, didu dd cd thd dugc gidi thich do
hdi gian qud trinh lam ngudi man sau ep ndng
an 2 trong trudng hgp nay dai han
- Phdn tieh kdt qud cho tren hinh 5c (x
iOO) khao sat dpc hudng dp eua mdu bdnh rdng
xich ed ky hidu BRX 3, nhung vi tri khao sdt thay ddi ddn vung gdn chdn rang, cho thay: td chiic td vi vdt lieu khdo sdt tai day cd edu tnic hat min vdi su phan bd ddng deu cua cac phan tu cau tnic cd mdu den (kich thudc rat nhd) trong pha nen ca ban mdu ghi va xen !an cac viing cau tnic cd sang Td chiic te vi vat lieu tren mau BRX 3 ed ddc tinh gidng nhu tren mau BRX 1 rdt rd net nhu d hinh 5a Tuy nhien, kich thudc hat edu tnic ndi chung d mdu BRX 3 nhd ban so vdi mdu BRX 1, didu do cd the rdupc giai thich bdi do vat lieu tai ciing khao sat gan chan rang trong qua trinh ep ndng ldn 2 de bien dang tao hinh prophin rang tii phdi sau ep ndng sa bp Ian
1 vdi lugng bidn dang ldn han nhieu so vdi vat lieu d trong than banh rang Do cudng do bien dang ciia vat lieu d viing gan chan rang vd trong rang la rat ldn, nen cac hat cau tnic hinh thanh d
do la cau tnic hat min, Tuy nhien, can luu y rang
do dac didm eiia bidn dang vat lieu xdp thidu ket tu kim loai bgt ma su hinh thanh cac hudng dudng chay cua cac hat cau tnic khdng ro net nhu ddi vdi vat lieu diic can thdng thudng Mac
du vay, trdn hinh 5c (x 500) cGng cho thdy cd
su khdc bidt giiia kich thudc cac hat edu tnic khdo sat dpc theo hudng ep so vdi kich thudc ciia chiing theo chidu ngang" hudng dp Su sap xdp ede hat edu tnie vdt lieu ed dinh hudng thidn
ve phia doc hudng ep, dieu do rat phii hgp vdi ly thuydt bien dang dec kim losii ndi chung '
TAP C H i CO KHf V I £ T NAM Sd 10 (Thdng 10 nam 2012
Trang 7NGHIEN cufu - TRAO eOl
- Phan tich kdt qua cho tten htah 5d (x
500) khdo sat dpc huang ep tai vung gdn chan
rang cud mdu bdnh rang xich cd ky hieu BRX
4, cho thdy: dac didm td chile td vi vdt lieu
mdu BRX 4 tuong tu nhu ttdn mdu BRX 3 Tuy
nhien, cdc phdn tu edu tnic cd mdu den o ddy cd
kich thudc hinh hpc ldn hon so vdi mau BRX
3, didu nay cd thd dupe gidi thich bdi do lupng
bidn dang deo cua mdu BRX 4 cdn d muc thdp
hon so vdi mdu BRX 3 Nhu ta da bidt, khi dp
ndng vat lieu bdt kim Ipai sau dp - thidu kdt hoac
dp ndng (vdt lieu xdp ndi chung) trong khudn
kin, thi bidn dang ddo se xdy ra chu ydu theo
phuong bidn dang chinh, tiic doc hudng dp Tuy
nhien, ttong cdng ttinh nghien ciiu ndy, co mdt
phdn vat lieu d vdnh ngodi cua phdi sau dp ndng
ldn 1 chiu bidn dang theo cd hai phuong dpc vd
ngang hudng dp, nhd do hinh thanh cac rang
cua bdnh rang xich tdy theo thidt ke cua khudn
dp ndng tinh chinh ldn 2 Vi thd, do dac tinh vat
lidu bi bidn dang la vat lieu xdp, nen cdn han
che bien dang deo theo phuong ngang hudng dp
bdng each tang dudng kinh phdi dp ndng ldn 1
so vdi dudng kinh dinh rang nham tao dieu kipn
cho v^t li?u chu yeu la chiu nen
3.4 Ddnh gia chung ve kit qua chi thir banh
rang xich HD-GF6
Tur cdc ket qua nghidn ciiu th\rc nghidm
da ttinh bay d tten, cd thd dua ra mpt sd danh
gia tdng hpp ve vide chd thu bdnh rdng xich
HD-GF6 trpng bd truydn dpng xich tdi xe may
HONDA bdng cdng nghd luydn kim bpt nhu
sau:
I) Bdt thdp hpp kim hda thdp dupe
nghidn trdn tir bdt sdt HOGANAS (Thuy Didn)
lam nen co sd va cdc nguydn td khdc nhu: Cu,
Ni, Cr, Mo, W, Tic vdi hdm lupng ddn 2 %
khdi lupng/mdi nguyen td, cd tdc dung lam tang
CO ly tinh vdt lieu sau dp vd thidu kdt (hoac sau
dp ndng - tuc thidu kdt ddng thoi dudi dp luc)
Vipc bd sung them C-graphit lam tang khd nang
nhipt luypn tao pha mactenxit, cdn tang Cr, Ni,
Mo thdnh thdp khdng ri Rieng ddi vdi Cu vdi
ham lupng khd ldn Id trudng hpp ridng bipt cda
sdt bdt va thep cd hifu qua hda bdn cao va hay dupe ling dung nhdt trong budc tao bpt nguySi lieu ddu vdp cua cdng nghd luydn kim b$t Sy
cd mat cua Cu nang cao co tinh cua hpp kim o tr?ng thdi ii khi ham lirpng Cu ldn hon 2,0 % khdi lupng, vd cd thd tidn hdnh hda gia dd cd su bidn Cling bdi tilt pha phan tan ndu ham lupng ddn 10 % Cu Vi thd, ttong cdng trinh nay, vifc chpn ham lupng cac nguydn td hpp kim hdad miic thdp vdn dam bdo dupe co tfnh vat lieu san thidu kdt d miic cdn thidt vira di^dd sir dimg ^ viec chd t?o bdnh rang ldm vide 6 didu kidn tiii trpng cd va dap va chiu mdi mdn cao 2) Vdt lieu bdt thep hpp kim hda thip bdt sdt H O G A N A S (Thuy Didn) dupe chpn.dj thi nghipm cd thanh phdn hda hpc nhu da chon gdm cd: [2 % Cu + 0,8 % C + 0,8 % Zn-Steoral + (0,5 + 2,5) % Cr + (0,5 + 2,5) % Ni + (0,5* 1,5) % W + Fe - cdn lai] Sau khi dp ndng so
bd ldn 1 trong khudn graphit vdi cdc chd dd thi nghidm nhu sau: dp l\tc dp ndng p^^ = 10; 20;
30 MPa (budc didu chinh la 10 MPa); nhift ii
dp ndng T ^ = 1200; 1250; 1300 °C (budc iik
chinh Id 50 °C); thdi gian giO nhipt te.n = 2,0; 2,5; 3,0 phiit (budc didu chinh 0,5 phiit) cd do xdp hiong ddi cao (yo= 35,333 + 26,666 %; 1)
po = 5,076 + 5,756 g/cm') Do vdy cdn phdi ti&
hdnh budc dp ndng tinh chinh trong khudn tm
loai dd ldm giam dp xdp, ddng thdi tao hint vdnh rang ngodi va Id rang then trong cua san phdm theo thidt kd mdu banh rang xich GF-6 ciia Nhat Bdn
3) Qua cdng doan dp ndng tinh chinh lan
2 ttong khudn kim loai, dp xdp vat lieu ttdn cac mdu bdnh rang xich HD-GF6 chd thit da giam xudng tdi miic dat gdn tuong duong kim loai diic can truyen thdng, cac Id vi xdp dupe cho
Id khdng dang kd: 1) y^ = 0,631 •*• 0,301 %, con mat dp tuong ling sau dp ldn 2 tang len tdi p,
= 7,80 •*• 7,826 g/cm' Kdt hpp vdi cac kdt qui
nghien ciru chup dn td chiic td vi vdt lipu tten cdc bdnh rang xich chl thu sau dp ndng ldn 2 cho thay du ydu edu ky thudt lam vide trong didu kipn chiu tdi trpng va ddp vd chiu mdi mon eao
TAP CHl CO KHi VIETNAM • Sd 10 (Thdng 10 ndm 2012)
Trang 8NGHliN cufu - TRAO D 6 |
4 i d : T L U ^
Tu nhftng npi dung trinh bay trdn ddy rut
ra cac kdt ludn nhu sau:
1) Dd dd xudt phuong an chd thu sdn
phdm banh rang xich HD-GF6 (lo^i Z = 14 rang)
trong bp truydn ddng xich tai xe may HONDA
bdng cdng nghe phdi hgp dp ndng sa bd ika 1 dd
tao hhih phdi h b h tru cd Id va ep ndng tinh chinh
ldn 2 dd t^o hinh prophin vdnh rang ngodi ddng
thdi vdi Id rang tiien Dp xdp the tich trung bmh
cua cdc phdi banh rang xich sau ep ndng so bd 1 ^
1 dat yo = 35,253 ^ 27,666 %, cdn mat dp hrong
ling chi dat po = 5,082 -^ 5,678 g/cm^ Dd x6p thd
tich trung binh cua cdc phdi banh rang xich sau
dp tmh chmh 1 ^ 2 dat y2 = 0,631 - 0,301 %; cdn
mat dd tuong ling sau dp ldn 2 t a i g ldn tdi p2 =
7,80 -^ 7,826 g/cm^ Dp cung d t r ^ g thai sau ep
ndng Ian 2 va Iam nguOi trong khdng khi dat HV
= 2328,75 ^ 2615,0 MPa Didu dd minh chiing ro
net cho tinh chat vat Iy cua v^t li^u bpt thep hgp
kim hda thdp cd thdnh phdn hda hpc dd chpn cdi
thien vd nang cao ddng kd trong qua trinh ep ndng tao hinh sdn p h ^ ddn miic gdn tr^ng thai kim loai ddc xit;
2) Qua vide nghidn cuu khdo sat vd chup anh td chue td vi vdt lieu bdt thep nhdn duge trdn
ca sd bpt sit HOGANAS h? [Fe Cu Cgrafit -Zn-Stearat] nghidn trgn thdm cde nguydn td nhu
Cr, Ni, W tai cac vung kdt cau d^c trung (than rang, chan rang, prophin rang) cda banh rang xich HD-GF6 sau ep ndng tinh chinh lan 2 dpc
vd ngang hudng ep cho thdy tat ca cdc mdu bdnh
r ^ g xich dugc khdo sat ddu cd edu tnic kim lo^i mang tinh chat dac trung cua cdng nghd luydn kim bdt, dam bao tdt tinh nang lam v i | c d didu kien tai trpng ed va dap vd chiu mdi mdn cao ciia banh rang xich truyen dpng xe may che thii •
Ngdy n h ^ bai: 24/8/2012 Ngdy phdn bifn: 15/9/2012 NgirM p h a n b i | n : GS, TS TV^n Vdn Dich, Vidn Nghidn cihx Ca khi
Tdi li^u tham khao:
[1] HdMinh Hiing (2000): "Nghien ciiu dp dyng cong nghe luy^n kim b^t che tao banh rSng mdy c6ng c\i (m = 2,2 = 28)", Bdo cdo Khoa hpc Chuyen de KHCND5.06-03, Vidn nghidn cim Ca khi, Hd Noi, 1998,120 trang; [2] D6 Dinh Luong (201 l):"Nang cao chat lupng chi tiet may hi hot thdp hgp kim hoa thdp bang phuong phap bidn dgng nong", Ludn dn Tidn sT Ky thuat, Vi?n Nghien ciiu Co khi, Hd Ndi, 13 trang;
[3], 6 5 Dinh Luong, Hd Minh Hung (2012): "Nghien cuu anh hudng ciia chd dd ep thieu kdt dudi ap l\ic ddn
dp xop vd mSt d0 vat li?u hot thep hgp kim hda thdp lam banh rdng", T?p chi Co khi Vi?t Nam, s6 TlO/2012
TAP CHf C O KHi VlfiT NAiVI • Sd 10 (Thdng 10 ndm 2012)