冷速对Au熔体凝固组织影响的分子动力学模拟

Molecular Dynamic Simulation of the Influence of Cooling Rate on Solidification Structure of Au Melt

为了研究液态金属Au凝固后微观结构随冷速的变化规律,通过分子动力学方法模拟液态金属Au的凝固组织,利用径向分布函数和HA键型指数法对最终构型进行分析.模拟结果表明:冷速在1.0×10^(11.0)~1.0×10^(14.5) K·s^(-1)之间时,Au熔体凝固后形成由晶体结构和非晶态结构组成的混合组织;冷速大于1.0×10^(14.5) K·s^(-1)时,凝固后形成非晶态组织.最大晶体团簇中,FCC结构原子随着冷速的增加而变少,HCP结构原子数量随着冷速的增加先增多后减少.

In order to study the change of microstructure with cooling rate after solidification of liquid metal Au,the solidification process of liquid Au was simulated by molecular dynamics method,and then the radial distribution function and the bond-type index method of Honeycutt-Andersen（HA）were used to analyze the final strctures.The mixture structures of crystals and amorphous structure form when the cooling rate ranges from 1.0×10^11.0 K·s^-1 to 1.0×10^14.5 K·s^-1.When the cooling rate is higher than1.0×10^14.5 K·s^-1,only amorphous structure forms in final.In the largest crystal clusters,with rise of cooling rate,the atom number of FCC structure decreases while that of HCP structure increases at first and then decreases.