Study On Micorstructure And Properties Of Cu-Mo-C Composites Fabricated By EB-PVD

There are the excellent physical and mechanical properties in copper and copper alloys,so they have been widely used in the electronicsand other industries.With the quick development of science and technology,especially the microelectronics industry,the traditional copper and copper alloys can’t meet these requests,especially both conductivity and strength.So the researchers developed copper matrix composite in recent years,which had high conductivity and high strength.Electron Beam Physical Vapor Deposition(EB-PVD),as a method for copper matrix composite,can almost evaporation any materials.EB-PVD fabricatedcompositesthat is difficult or impossible to conventional process,meanwhile considering simple procedure,rapid deposition speed,convenient control of element conent,size and distribution;it can be used as a new process to fabricate Cu matrix composites.Cu-Mo-C micro-laminated composites and dispersion strengthened Cu-Mo-C compositeswere fabricated by EB-PVD.HF infrared absorption C/S instrument,SEM,EDS,XRD,XPS,TEM were used to characterizethe compositions,phase and microstructure of Cu-Mo-C composites.HMV-1T type micro-sclerometer,KT2511A type low DC resistance tester,3010 type electrical universal material testing machine and UMT-2 were used to test microhardness,conductivity,tensile test and frictionperformanceof Cu-Mo-C composites.The study results of Cu-Mo-C micro-laminated composites showed:the thickness and distance ofMo-C micro-laminated were 1.5μm and 18μm respectively;Cu micro-laminated was columnar crystals which was less than 4μm;the maximum tensile strength,yield strength and elongation were 271 MPa,251 MPa and 3.4%at room temperature;the ductility and toughness were better at 300 ℃,meanwhile the elongation was 8%;the conductivity was 88.8%ISCA.Dispersion strengthened Cu-Mo-C composites was found by studies:the dispersed particle was Mo2C and less than 20nm;there were the preferential orientation of Cu(111)and twin crystal of Cu(110);the hardness was 1577.8MPa,the dispersion strengthening and grain strengthening were 23.6%and 60%in all strength respectively;the maximum tensile strength,yield strength and elongation were486MPa,426MPaand 3.8%at room temperature;dispersion strengthened Cu-Mo-C composites showed high temperature embrittlement with the rise of temperature and the elongation was only 1.8%at 300℃;the conductivity was 82.1%ISCA;the fricition coefficient was 0.2.