HMX晶体加工及力学性能模拟

HMX Crystal Processing and Simulation of Mechanical Properties

通过分析HMX晶体的精加工过程,发现切割速度对晶体的加工质量有重要影响,而且速度大小需要随着温度和晶面的变化而不断调整。采用分子动力学(MD)方法,在COMPASS力场下模拟了HMX晶体(011)和(010)晶面在不同温度下的力学性能。结果表明:随着温度的升高,晶面的杨氏模量(E)、体积模量(K)、剪切模量(G)、K/G呈先上升后下降趋势,说明HMX晶体的刚度、断裂强度、硬度、韧性均随温度升高而先升高后下降,其中(011)面和(010)面的各模量分别在308K、298K达最大值,预测(011)面的最优加工温度在308K左右,(010)面的最优加工温度在298K左右,这与实际加工过程相符。

Through analyzing the HMX crystal processing, it is found that the cutting speed is very important to the crystal carving, and should be constantly changed to adjust the variation of crystal face and temperature. By molecular dynamics（MD）, the mechanical properties of（011） face and（010） face of HMX crystal were simulated in different temperatures with COMPASS force filed. The results show that, with the increasing of temperature, Young modulus（E）, bulk modulus（K）, shear modulus（G） and the ratio of K/G rise in the first stage and then decrease, which indicate that the stiffness, breaking strength, hardness, tenacity of the HMX crystal all rise firstly and then decline with the temperature raising. The modulus of（011） and（010） reached maximum at 308 K and 298 K respectively. The optimal processing temperature of（011） face is predicted of 308 K and that of（010） face is 298 K, which according with the actual processing.