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用分子动力学(MD)模拟方法研究在轴向压缩下,冷却速率、应变率、环境温度、裂缝对Cu64Zr36二元非晶合金力学性能的影响。在模拟中,采用EAM势函数表述原子间的相互作用。计算结果表明:非晶的弹性模量和抗压强度都比晶体试样大一倍多,而当应变≥15%时两种试样的流动应力几乎相等;冷却速率缓慢得到的非晶试样由于原子发生重组变疏松,产生剪切带,而冷却速率较快得到的试样则没有发生重组;试样的弹性模量、抗压强度和流动应力对应变率变化很不敏感;随着环境温度的升高,流动应力、抗压强度和弹性模量降低;有初始裂纹的试样剪切带集中,从裂纹尖端开始,与加载方向呈45o方向扩展。
The effect of cooling rate, strain rate, ambient temperature and crack on the mechanical properties of Cu64Zr36 binary amorphous alloy under axial compression was investigated by molecular dynamics (MD) simulation. In the simulation, EAM potential function is used to describe the interaction between atoms. The calculated results show that the elastic modulus and the compressive strength of the amorphous samples are both more than twice that of the crystal samples, while the flow stress of the two samples is nearly equal when the strain is greater than or equal to 15%. The amorphous samples with slower cooling rate As the atomic reorganization becomes loose, resulting in shear band, and the cooling rate of the sample obtained without reorganization; sample elastic modulus, compressive strength and flow stress is very sensitive to changes in strain rate; with the environment The increase of temperature, the flow stress, the compressive strength and the modulus of elasticity decrease. The shear band with the initial crack is concentrated, starting from the crack tip and spreading in the 45o direction with the loading direction.