Molecular Dynamics Simulation Of Deformation Behavior Of Zr₅₀Cu₅₀ Amorphous Alloy

As we know,deformation process of bulk amorphous alloys at high strain rate andlow temperature is achieved mainly through the formation and propagation of shearbands.However,the study of the deformation behavior of the nano-sized amorphous alloyhas been limited to experimental conditions.In this paper,we study how size,strain rate andtemperature affect the deformation behavior of the nanoscale Zr₅₀Cu₅₀amorphous alloy bymolecular dynamics simulation.Simulation results show:the tensile deformation of cylinder model with diametersbetween6.5nm to10.4nm transitions from inhomogeneous deformation by formation ofshear bands to uniform plastic deformation with the decreasing size of Zr₅₀Cu₅₀amorphous alloy.Meanwhile,because of the size-effecs and the change of deformationmechanism, its deformation capacity is also increased;As the strain rate increasing,theamorphous alloy appeared the same change of deformation mechanism and the fracturestrength is also improved.The deformation behavior of amorphous alloy also is very much sensitive totemperature.When the temperature increases from100K to900K,breaking strength of theamorphous alloy has shown a significant decline and the peak of stress-strain curve shiftleft during the deformation process.This phenomenon is mainly because that a rise intemperature has exacerbated atomic transition behavior, generated more free volumetherefore speeded up the yield of the amorphous alloy.During the research process of thedeformation behavior of amorphous alloy near the supercooled liquid regiontemperature,as the temperature increasing from800K to900K,the model deformationbehavior of shear band gradually weakened until disappears.