H6 K^ Thanh vd Btg Tap chi KHOA HOC & CONG NGHE 176(16): 5 5 - 5 9
TONG HOP VAT LIEU Fe-Cu-Ai BANG PHlTONG PHAP HOP KIM HOA CO HQC
Ho K^ Thanh'-', Nguyen D | n g Thuy^
'Trudng Dai hoc Ky ihugt Cong nghiep - DH Thdi Nguyen.
^Trudng Dai hoc Bach Khoa Hd NQI TOM T A T
Bai bio nay trinh bay m$t s6 ket qua nghien ciru ting hgp he vat liSu Fe-Cu-AI vdi muc dich iing dung trong chl tao bgc Idt chju tai trong Idn bing phuang phip hpp kim hda co hpc. Kit qua phan tich nhilu xa tia X hon hpp cho thay, dung djch rln Cu-AI da dugc hinh thanh trong qua trinh hgp kim hoa. Vdi ap luc ep trong pham vi 3l2-;-390 MPa. nhiet dp thieu kit trong khoang 850-^950''C v i thdi gian thieu ket trong 1,0 gid thi cic mlu vat lieu nhan dugc co tong dp xop trong khoang 20-H27%. Dp xop ciia cac mau vat lieu giam khi ap lyc ep va nhiet'dp thieu ket tang. Ti le 16 xop hd ciia hlu het cic mlu dgt tren 80%. Dp ciing ciia mau vat lieu nhgn dugc trong pham vl tir 47 din 63,4 HRB va tang khi thdi gian hop kim h6a co hpc tang. He vit liSu Fe-Cu-AI hiia hen sg dip ling tflt cic yeu cau doi vdi vgt lieu lam bac 16t chiu tai trpng Idn.
Til- khda: vdt lieu d trugt; hgp kim hoa ca hoc. dung dich ran, luyen kim bgt; xop, do cung.
DAT V A N DE
Vgt lieu trSn c a sd ddng (Cu-base) dugc biet dSn la vat lieu c a ban de chS tao cac Ioai bac lot do chiing cd c a tinh t u a n g dfli cao, he so ma sat trugt khi lam viec vdi cac tryc thep tucmg dfli nhd (trong khoang 0 , 2 - 0 , 3 ) [ I ] , co kha nang tu bfli tron va cd the tao d u g c do xdp phii hgp dS ngam dau bdi tron trong qua trinh lam viec lau dai. Do do, vat lieu bac Idt tren c o sd ddng d u g c sii dung trong ca truong hgp tai trgng nhd va trudng hgp tai trpng Idn [ I ] . Tuy nhien, trong t h y c tS cac bac lot sd dung vgt lieu nay thudng cd cau tgo gdm hai Idp, Idp bSn trong la vat lieu trSn c a sd ddng va la Idp vd ngoai la thep. Do vgy, viec c h l tgo cac bgc lot dgng nay la tuong ddi phuc tgp va d i t dfl, dgc biet la trong trudng hgp chiu tai trpng Idn. Do dd trong thdi gian gan day, tren the gidi da cd mpt so cdng trinh nghien cuu c h l tao cac logi vat lieu mdi trSn c a sd nin thep u n g dyng lam cac bgc Idt chiu tai trpng cao, chang ban he Fe-Cu-C, Fe-Cu-Al, Fe-Cu-AI-MoSj,... [2-5]. Cac vat lieu mdi nay dam bao bac lot dugc chS tao la mflt khoi duy nhat [2,3,5]. Dung djch ran Cu-Al cd dp Cling va dp bSn cao, chiu mai mdn tdt, ma sat vdi thep nhd. S y xuat hien cua dung djch ran Cu-AI trong nen Fe se giup vat lieu nhan
'Tel 0984 194198. Email: hlcvlhanh@lnut edu.vi
dupe cd he sd ma sat vdi thep nhd, ddng vai trd la nhan tfl gia efl dS nang cao dp ben va cai thien dp ciing ciia vat lieu nen F e . . . [6-9].
Bai bao nay se trinh bay mdt sfl nghien cdu vS tdng hgp he vgt lieu Fe-Cu-AI b i n g phuang phap hgp kim hda c a hoc va mgt sfl ket qua danh gia ve tflng dp xdp, kha nang tham dau, dp Cling cua vat lieu nay.
K t T H U A T THLTC N G H I E M
DS tao vat lieu bac lot, ti le giua cac logi hot Fe:Cu:AI dupe lya chpn t u a n g ling la 0,6:0,35:0,05 tinh theo trpng lupng. Tru'dc tien cac loai bpt t h u a n g mai Cu (99,97%) va Al (99,2%) dugc phdi trdn theo ti le 27gr Cu • 6gr Al va dugc hop kim hda c a hpc trong khoang tir Oh den 8h bang may nghiSn canh khuay dung trong mdi trudng bao ve la khi Ar. Tang nghiSn b i n g thep dugc lam mat b i n g n u d e tuan hoan. Bi nghien bang thep tdi Cling cd d u d n g kinh tii 8-^10mm, ti le bi : bpt d u g c lua chgn la 10 : I. Sau dd, hdn hgp bdt Cu-AI dupe phdi trdn them bdt thuong mgi Fe (99,9%) vdi ti Ie 2 (Cu-AI) : 3 (Fe) va dugc trdn ddng deu hda thanh phan bang may nghien bi dang tang trong. Tiep do, hdn hgp bdt Fe-Cu-AI d u g c ep thanh cac mau hlnh tru CO d u d n g kinh d = 16 mm va chieu cao h = 15 mm bang may ep thiiy luc S T E N H 0 J vdi ap lyc ep trong pham vi tir 234 MPa dSn 390 55
Ho Ky Thanh vd Dtg Tap chi KHOA HOC & CONG NGHE MPa. Tiep dd, cac mau ep dugc thieu ket
trong Id dien trd Linn 1300 d cac nhiet dg 850°C, 900°C va 950°C trong cimg khoang thdi gian la 1,0 gid dfli vdi tat ca cac mau.
Trong qua trinh thyc nghiem, phuong phap nhieu xa tia X dugc su dung dS danh gia qua trinh hgp kim hda c o hpc giira Cu va AI. Dp xdp tflng ciia mau dugc xac djnh bang phuong phap Ac-si-met, ti IS Id xflp hd dugc xac djnh bang each ngam mau trong nude va so sanh vdi mau khi khfl, thiet bj dugc sir dung la can dien tir Scientech co dp chinh xac den I0~ gam. Mat cat cua mau vat lieu nhgn dugc sau khi thiSu ket duoc xac djnh bang phuang phap SEM tren kinh hien vi dien bi quet Tescan. D o ciing ciia mau dugc xac djnh bang may do do ciing Duramin Stmers, su dung thang do HRB.
KET QUA v A B A N LUAN
P h o nhieu xa tia X c u a h o n h o p bdt sau khi h g p k i m hoa cor hoc va nghien t r p n d o n g deu t h a n h p h a n
Ket qua phan tich nhieu xa tia X trSn hinh I cho thay, sau,khi hgp kim hoa mdt khoang thdi gian xac dinh, c u d n g dp cua cac peak Cu
va Al giam, thgm chi mpt vai peak bi biin mat khi tang thdi gian nghien. Tii dd co thi ket luan la qua trinh hgp kim hda da xay ra trong qua trinh nghien. Sau 4h nghien, bit diu CO su chong ISn nhau cua hai peak manh nhai.
Dieu nay cho thay su di chuySn ciia cac peak Al bdi vi Fe khdng lien quan dSn qua trinh hpp kim hda c a hpc do dd cac peak ciia Fe van giQ'a nguyen vj tri. Dieu nay phii hpp voi cac ket qua cdng bfl trudc day vS kha nang hinh thanh dung djch ran Cu(AI) bing phucmg phap hop kim hda c o hpc [6]. Dl dang nhgn thay cd sy thay dfli nhat djnh ciia cac peak Cu-AI. Rd rang, co mdt peak Al thay ddi VI tri. Hien tugng nay cd thS dugc giai thich do nhan dugc nang lupng cao tii qua trinh nghien hpp kim hoa, cac nguyen tir Al da khuech tan vao trong nSn Cu de tgo nen dung dich ran p-Cu(AI). Pha mdi nay se co tac dung hda ben cac mau, giiip cho chiing c6 dp cimg cao hon. Ngoai ra, cd thS dS dang nhan thay rang cac peak Fe khdng thay dii giua cac mau, nguyen nhan bdi Fe khflng bi hgp kim hda trong qua trinh nghien.
6 0 0 0 -
0 -
_-,1...
•
• 1
li l-r
i;-
1 •
•
•
— ( f i .
* Solid solution
• F e
• C u
• A l
•
•
• •
Hinh 1. Phd nhiiu xa tia X ctia hdn hftp bat Fe-Cti-Al a cac thdi gian hap lum hoa Ithac nhau
Ho Ky Thanh va Dtg Tap chi KHOA HQC & CONG NGHE 176(16): 5 5 - 5 9 K e t q u a x a c d i n h t o n g d o xop v a ti IS l5 x o p
h d c u a v a t liSu
DO xop la thdng so quan trgng ciia vat lieu lam bac Idt. Cac 16 xflp dong vai tro nhu cac i tri chiia dau bdi tran, trong qua trinh chju tai, dau t u cac 16 xflp se d u a c tiet ra tren be mat tiep xuc giiia bgc Idt va true giiip giam he so ma sat, giam mon va tang tudi thg cua san pham bac Idt. Ket qua x a c dinh tflng dp xdp bang p h u a n g phap d u g c liet ke trong bang 1.
Co the nhan thay, d ciing mot nhiet dp thieu ket, khi tang ap luc ep ddng khfli thi tdng dp xdp ciia mau nhan d u p e sau khi thieu ket giam. DiSu nay la hien nhien vi khi tang ap lyc ddng khfli, cac hat bdt bj biSn dgng nhieu han va sap xep xit chat h a n , mat dp khoi ep Idn hon va do dd dp xflp cua mau vgt lieu Fe- Cu-Al nhgn d u p e se nhd hon.
COng tir bang 1 cd thS nhan thay, vdi ciing mpt ap lyc ep, nhiet dp thieu ket cimg cao thi mau vat lieu Fe-Cu-Al nhan dugc cd dp xflp cang giam. R6 rang la trong ban than khfli Sp khi thieu ket ngoai vat lieu c a sd nen Fe con CO sy xuat hien cua Cu, Al d u va dung dich
Bang L Dd xop tdng vd do cung ctia mdu vdt lieu Fe-Cu-Al nhdn dugc i luc ep vd nhiit dd thieu kit khac nhau
ran Cu-AI. T u a n g u n g vdi khoang nhiet dfl thieu k i t dugc lya chpn (850-^900°C) thi ban thSn Cu de bi bien mem, dung dich rln Cu-AI va ban than Al da d tren nhiet dp nong chay vi vgy chiing se dien day vao cac Id xdp san cd gifla cac hat bpt Fe ciia mau sau khi ep ddng khoi. Nhiet dp thiSu ket cang cao thi ngoai viec Al, dung djch ran Cu-AI chay long thi Cu cQng bi bien mem, tham chi cd kha nang chay long mdt phan vi vay dp xdp ciia mau nhgn dugc sau khi thieu kSt giam.
Ket qua xac djnh ti IS Id xdp h d ciia cac mau vat lieu (la cac 16 xdp lien thdng vdi nhau) thdng qua viec danh gia kha nang ngam n u d e cho thay, ti IS xdp h d dat tren 8 0 % ddi vdi hau het cac mau. Vdi cimg mflt ap lyc ep thi ti le Ifl xdp lien thflng cua vat lieu giam khi tang nhiSt d^ thiSu ket va tuong tu, vdi ciing mpt nhiet dp thieu ket thi ti le 16 x6p liSn thong cijng giam khi ap luc ep ddng banh tang. DiSu nay dugc giai thich tu'ong ty nhu dfli vdi tdng dfl xop cua cac mau vat lieu nhan dugc sau khi thieu kit.
u khi thieu ket luang dng vdi dp T h *
tU' 01 02 03 04 05 06 07 08 09 10 II
Thdi gian hirp kim hoa (h)
0 0 0 0 4 4 4 8 8 8 8
Ap luc ep (MPa)
234 390 234 390 312 312 312 234 390 234 190
Nhiet d9 thieu Itet C O 850 850 950 950 900 900 900 850 850 950 950
Tttng tio xop
(%)
27 23 25 27 23 24 24 26 20 27^^
Dd ciillg (HRB) 48.5 56.0 52.8 57.0 57.1 57.2 53.0 50.0 63.1 59 0 f>nii
Hinh 2. Anh SEM mdt cat doc mdt mdu vdt liiu Fe-Cu-Al sau khi thiiu kit a 900 °C vdi thai gian hgp kim hda ca hgc 8h
H i K.)i Thanh vd Btg Tap chi KHOA HOC & CONG NGHE 176(16): 3 3 - a y K e t q u a a n h c h o p m a t m a u v a t lieu
Hinh 2 la mat c i t doc cua mpt m l u vat lieu Fe-Cu-AI dugc ep vdi ap Iyc 312MPa va thieu k i t d SSO^C trong thdi gian l.Oh. Cd t h i de dang nhan thay cac Id xop co dang da cgnh, kich thudc cac 16 xflp Idn trong khoang 100^200iim, phin Idn chiing dugc lien thdng vdi nhau bdi cac Id xflp nho hon. Day la mpt minh chung cho cac ket qua xac djnh ti IS Ifl xflp hd ciia vat lieu nhan duoc sau khi thieu kit. D i l u nay hiia hen vgt lieu Fe-Cu-AI co kha nang t h i m va giy dugc dau bfli tron de ty bfli tron trong qua trinh lam viec.
K e t q u a x a c djnh d o cirng c d a v a t lieu Ket qua xac dinh dfl ciing ddi vdi mdi mau vgt lieu dugc the hien tren bang 1 la gia tri trung binh ciia dp cung do dugc tai ba diSm khac nhau tren bS mat m l u (hinh 3)
Hinh 3. Anh chup mdu duac du do cung Til' ket qua do dp cung trong bang cd the nhgn thiy, dp Cling cua cac mau vat lieu Fe-Cu-AI CO xu hudng tang khi tang thdi gian boat hoa.
D i l u nay c6 the dugc giai thich bdi sy tgo thanh dung dich ran Cu-AI, pha nay cd dp Cling va dp ben cao, trong nen Fe giup cai thien dfl ciing cua vat lieu nen. Ket qua do dg cung cua he vat lieu nay t u a n g dfli phii hgp vdi cac cdng bfl trudc day vS dp cung ciia cac loai vat lieu iing dung lam bac Idt chju tai trpng Idn.
KET LUAN
He vat lieu Fe-Cu-AI vol muc dich ling dyng trong chS tao bgc lot chiu tai trpng Idn da dugc tflng hgp thanh cflng bang phuong phap hgp kim hda c o hgc, Dudi tac dung cua nang lupng va dap tir bi trong qua trinh nghien, dung djch ran Cu-AI da dupe hinh thanh sau
khoang 8 gid. Cac mau vgt lieu Fe-Cu-Al nhan dupe co tong dp xflp trong khoang 2 0 - H 2 7 % vdi ap lyc ep trong phgm vi 312-^390 MPa, nhiet do thieu ket trong khoang 850-^950°C va thdi gian thiSu k i t trong 1,0 gid thi tong dp x6p giam khi tang ap luc ep ddng banh va tang nhiet dp thieu ket. Ti IS cac 16 xflp lien thflng ciia hau het cac mau dgt tren 80%. T u a n g t y tflng dp xflp, khi tang ap lire ep dong banh va tang nhiet dp thiSu ket thi ti ie lo xflp liSn thflng giam. D p cu'ng ciia mlu vat lieu dgt d u g c trong pham vi tir 47+63,4 HRB. He vat lieu Fe-Cu-AI hua hen se dap ung tflt cac yeu cau ddi vdi vat lieu lam bsic Idt chiu tai trpng Idn.
L6I CAM ON
K i t qua trinh bay trong bai bao la mpt phin nghien ciru ciia de tai Khoa hpc va Cong n ^ e cap tru'dng, ma s6 T2016-64, tap thS tac gia xin chan thanh cam on trudng Dgi hpc Ky thuat Cflng nghiep (Dai hpc Thai NguySn) ho trg v l mat thii tuc, tai chinh dS thyc hien cong trinh nay.
T A I LIEU T H A M K H A O 1. S Dhanasekaran and R Gnanamoorthy (12/200^
Development of self lubricating sintered steels fon, tribological applications-, Intemational Symposiuin of Research Students on Materials Science and Engineering, Chennai, India.
2 T KQ?akomeroglu, G. Purfek, O Saray, I, Kara (10/2008); Investigation of friction and wear behaviours of CuSnlO alloy in vacuum-, J.
Achievements in Materials and Manufacturing Engineering, Volume 30, Issue 2, pp. 172-176.
3. Yoshikiyo Tanaka, Masanori Ueyama, Takemori Takayama (2003); Development of New Materii^
for Special Oil-Impregnated Bearings-, Komat'su Technical Report, Vol. 49, No 152, pp. 1-5;
4. W.A. Glaeser (1983); Wear properties ofhearf loaded copper-base bearing alloys, J. Metals, Metallurgical Society of Aime, pp. 1-5.
5. Trent S. Ward, Wenliang Chen, Mirt;o Schoenitz, Rajesh N. Dave, Edward L. Dreian (2005); A study of mechanical alloying processii using reactive milling and discrete elemeii modeling; Acta Materialia 53, pp. 2909-2918.
6. C. Suryanarayana (2001); Mechanical alloyini and milling; Progress in Materials Science 46, pp.
1-184.
58
Hd K^ Thanh vd Dig Tap chi KHOA HOC & CONG NGHE 176(16): 55 - 59 7. Tianmin Shao, Xiankun Cao, Eric Fleury, Do- 9. yuji Enomoto and Takashi Yamamoto (1998);
Hyang Kim, Meng Hua, Dao Se (2004); ., , • , • , , . u 1 • T •u.^i^n,,, T ., 7 . , , , . J- , , ., ^ New materials in automotive tribology; I nbology Iribological behavior of plasma sprayed Al~Cu-
Fe+Sn quasicryslalline composite coatings; J. Letters 5, pp. 13-24.
Non-Crystalline Solids 334&335, pp. 466-*70. 10. Yong-Suk KimU, Yong-Hwan Kim (1998);
8. Jean-Marie Dubois (2000); New ;j/-05pec/i/rom sliding wear behavior of FesAl based alloys;
potential applications of quasicryslalline . ^ . - i c - J T - - • A->CO materials; Materials Science and Engineering ^^*^™'^ S^'^"'^*^ ^ ' ' Engineering A258, pp.
294-296, pp. 4-9. 319-324.
S U M M A R Y
F A B R I C A T I O N OF T H E Fe-Cu-AI A L L O Y B Y IVIECHANICAL A L L O Y I N G Ho Ky Thanh'*, Nguyen Dang Thuy^'*
University ofTechnology - TNU
^ Hanoi University of Science and Technology This paper presents some results from synthesizing the Fe-Cu-AI alloy system to apply in high load bearings by mechanical alloying. XRD pattern results showed that solid solution Cu-AI was formed during milling. Most material samples had total porosity in range of 20^27% when the compress pressure in range of 312-r390 MPa, the sintering temperature in range of 8504-950°C and sintering time in 1.0 hour. The total porosity decreased when compress pressure and sintering temperature increased. Most samples had open-pore ratio higher than 80%. The hardness of samples were in range of 47-^63.4HRB and increasing when milling time increased. The Fe-Cu-Al alloy system promise to satisfy the demand of high load bearing materials.
Keywords: bearing material; mechanical alloying: solid solution; metallurgy: porous; hardness
Ngdy nhgn bdi: 01/11/2017; Ngdy phdn bifn: 19/11/2017; Ngdy duyet ddng: 05/01/2018 Tel: 0984 194198, Email: [email protected]