变质处理对过共晶铝硅合金组织和性能的影响_林家平

,,,,,(中南大学材料科学与工程学院,长沙410083):通过在铸造过程中对熔体进行二元和三元变质处理,制备了硅质量分数为18%的A390过共晶铝硅合金;通过金相分析扫描电镜观察拉伸性能测试耐磨性能测试等手段研究了变质处理对A390过共晶铝硅合金组织和性能的影响结果表明:A390合金经过变质处理后,初晶硅棱角得到钝化,尺寸小于30Lm,共晶硅出现球化,晶粒尺寸减小;变质后合金力学性能明显提高,其中经三元变质处理后其室温抗拉强度与伸长率较未变质处理的分别提高了31%与150%;耐磨性能也有一定程度的改善,三元变质处理后的磨损机理以微观切削为主:铝硅合金;变质处理;显微组织;力学性能;耐磨性能:TG143:A:1000-3738(2010)03-0031-04InfluenceofModificationonMicrostructureandMechanicalPropertiesofHypereutecticA-lSiAlloyLINJia-ping,XUJian-qiu,XIAOYu-de,WANGWei,PEIFei,QIAOXiang(SchoolofMaterialsScienceandEngineering,CentralSouthUniversity,Changsha410083,China)Abstract:TheA390hypereutecticA-lSialloywith18wt%Sicontentwaspreparedthroughthemeltmodifiedbybinaryandternarymodifiersduringthecastingprocess.TheinfluenceofmodificationonmicrostructureandmechanicalpropertiesofA390hypereutecticA-lSialloywasinvestigatedbyopticalmicroscopyanalysis,scanningelectronmicroscopyobservation,wearresistancetestandtensilestrengthtest.TheresultsshowthatafterthemodificationofA390alloy,thecornerangleoftheprimarySiwasinactivated,anditssizewasbelow30Lm.EutecticSiwasspheroidized,andthegrainwasrefined.Mechanicalpropertiesofthemodifiedalloywereimprovedapparently.Afterternarymodification,comparedtonon-modification,theelongationandtensilestrengthofA390alloyatroomtemperaturehadbeenincreasedby150%and31%,respectively.WearresistanceoftheA390alloywasalsoimproved.Thewearresistanceinternarymodificationwasmainlymicroscopiccutting.Keywords:A-lSialloy;modification;microstructure;mechanicalproperty;wearresistance0A390,,,[1-4],,,:2009-02-26;:2009-12-14:(1982-),,,:,,,,,,[5-6][1-4],,[7-8],,,#31#34320103机械工程材料MaterialsforMechanicalEngineeringVol.34No.3Mar.2010,,-----A390,199.9%99.9%A-l30SiA-l50CuA-l10Mn(,)A-l18S-i4.5Cu-0.6Mg-011MnCRL-D760e,C2Cl6,A-l10LaA-l10SbCu-13PA-l5T-i2B,5min,A-l10La(0.6%),5min,A-l10Sb(0.008%)A-l5T-i2B(0.6%);,900~950e,Cu-13P(0.67%),60min,760eA-l10La(0.6%),5minA-l10Sb(0.008%)A-l5T-i2B(0.6%)5min,720e,130e15mm@115mm15mm@10mm,Cr2O3,Keller(0.5%HF+1.5%HCl+2.5%HNO3+9515%H2O),Polvar-METGB/T6397-1986R16,CSS-400,0.2mm#min-1,6CETRUMT-3,9.5mm(62HRC),19mm@12mm@12mm,800#,0.1mgShimdzuAUY220,,,5Hz,100N,30minKYKY-2500(SEM);QUANTA-200(SEM)22.11,A390,50Lm50%,;,,,,,,30Lm;,,,,;,,,[9-11],(a)(b)(c)1A390Fig.1Microstructureoftheas-castedA390alloyswithdifferentmodificationmethods:(a)withoutmodification;(b)binarymodificationand(c)ternarymodification#32#,:,1(b),,A-l5T-i2B,,;,,TiAl3TiB2,TiB2[12]Al2Ti2B,1,,,,,,,AlP,,,,,,,;,,,,,,,,A-l5T-i2BAlP,[13-15]2.21,A390,;15.1%,31%;150%1A390Tab.1TensilepropertiesofA390alloyswithdifferentmodificationmethodsRb/MPaD/%1320.21520.31730.52.32,A390,,,,2A390Tab.2FrictionandwearproperitesofA390alloyswithdifferentmodificationmethods/mg0.3080.290.3040.270.2970.26,,,,,,,,,[16]2,,;,,M,,,3(a),A,B,,3(b),(c),,,,,,,,,,;,,,,,,,,,,,,#33#,:(a)(b)(c)(d)(e)2A390Fig.2WearsurfaceandweardebrismorphologyoftheA390alloyspreparedbydifferentmodificationmethods:(a),(b)wearsurfacesofA390alloyswithoutmodification;(c),(d)wearsurfacesofA390alloyspreparedbybinarymodificationand(e)wearsurfaceofA390alloypreparedbytenarymodification3(1)A390,;(30Lm),,,(a)MEDS(b)AEDS(c)BEDS3A390MABEDSFig.3EDSspectraofM,AandBonwearsurfaceofA390alloyspreparedbydifferentmodificationmethods:(a)EDSspectraofMonwearsurfacewithoutmodificationandwithbinarymodificationand(b),(c)EDSspectraofAandBonwearsurfacewithternarymodification(2),A390;,31%150%(3)A390,,;:[1],.[J].,1998,12(3):57-62.[2].[J].,2004(1):1-7.[3],,,.[J].,2000(5):1-3.[4],.[J].,1999(1):1-5.[5],,.[J].,2005,19(5):42-45.(60)#34#,:,;4.01%,,,,,,;,[8],,5,36,7,,4.01%(a)3(b)6(c)75Fig.5ThewearappearanceofhardfacinglayerswithdifferentBcontents:(a)sample1;(b)sample6and(c)sample73(1);4.01%~4.95%,(2);0%~4.01%,,,,,;4.01%;:[1].[M].:,1985.[2].[J].,1978,14(6):1-15.[3].[J].,2000,22(2):8-14.[4],,,.B2O3-MgO-SiO2-A12O3-CaO[J].,1996,19(6):637-641.[5],.BRE-SiCr-Mn[J].,1985,37(3):1-6.[6],,,.[J].,1996,64(1):27-30.[7]IZCILERM,CELIKH.Two-andthree-bodyabrasivewearbehaviourofdifferentheat-treatedboronalloyedhighchro-miumcastirongrindingballs[J].JournalofMaterialsProcess-ingTechnology,2000,53:237-245.[8],,,.[J].,2007,12(3):69-72.(34)[6],.[J].,1995,15(1):61-66.[7],.A1-Si[J].,1997,24(6):48-50.[8],.A1-Si[J].,1995,19(10):6-9.[9].[J].,1990(3):12-14.[10],,.[J].,2002(1):107-110.[11].[J].,1998,21(5):1-2.[12],,.Al2Ti2B2RE[J].,2005,26(9):774-778.[13],,,.A-lP[J].,2003(5):18-22.[14],,,.A-lSiP[J].,2003(1):22-23.[15],,,./0A-lSiA-lP[J].,2001,9(2):211-214.[16].A-lSi[D].:,2000.本刊邮发代号:4-221定价12元全年144元欢迎订阅#60#,: