Effect Of Ceramic Rolling And Cryogenic Treatment On The Mechanical Properties Of Cu₄₂Zr₄₂Ag₁₀Ti₆ Amorphous Alloy

Due to its excellent plastic deformation and glass-forming ability,CuZr-based metallic glass has wide application prospects.In this paper,the research object of Cu42Zr42Ag10Ti6 amorphous alloy was processed by ceramic rolling and cryogenic treatment process,and the evolution of mechanical properties,thermal properties and microstructure of this amorphous alloy were studied respectively.Through the ceramic rolling process,the Cu42Zr42Ag10Ti6 amorphous alloy can be deformed at a large deformation rate(0?0.5s-1)without fracture.In this experiment,the amorphous alloy samples with 5%and 10%deformation degree exhibite excellent mechanical properties.The as-cast sample has almost no plasticity,while the as-rolled sample has a greatly improved compressive plasticity.The amorphous alloy sample with 5%thickness reduction ration has the largest compressive plastic strain of 24.3%.The morphology of shear band on the cross section of the samples after ceramic rolling also shows a certain change tendency.The shear bands are uniformly distributed on the sample with 5%deformation degree,accompanied with somebifurcated secondary shear bands.However the as-rolled sample with 10%thicknessreduction ration have more complex shear bands,and some shear bands join together.to form the highly extended shear bands.The change of shear bands' morphology leads to the different mechanical properties for the samples with different deformation degree.Also the structural relaxation enthalpy of the as-rolled samples are lower than the as-cast sample.By studying the mechanical properties of Cu42Zr42Ag10Ti6 amorphous alloy with different cryogenic treatment time,it can be found that the microhardness and compressive strength of amorphous alloy tend to increase with the cryogenic treatment time increasing.After seven days' cryogenic treatment on the amorphous sample,the microhardness and largest compressive strength of the specimen increased 44Hv and 200MPa respectively,as compared with the as-cast sample,also the largest compressive plastic strain of the specimen has been greatly improved to 23.5%.In addition,a series of thermodynamic parameters of the amorphous samples after cryogenic treatment were detected by DSC technique.It can be found that the amorphous samples after cryogenic treatment exhibit lower structural enthalpy Er than the as-cast sample.The results show that the effect of cryogenic treatment on the mechanical properties of Cu42Zr42Ag10Ti6 amorphous alloy is the result of many factors.