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本文探讨了多孔ＴＮＴ炸药中热点形成的粘塑性塌缩机理。在研究孔隙周围介质的粘塑性运动和由此引起的加热时，考虑了熔化效应，并对所建立的模型进行了数值计算。结果表明，在约３ＧＰａ的较低幅值冲击波加载下，受熔化影响，在具有不同尺寸的孔隙边界附近，熔化区温度均保持在熔点附近，而熔化区的存在保证了加热层具有一定的深度。对大颗粒样品，由于孔隙塌缩过程中熔化区的不断扩大，在熔化区中屈服强度为零，粘性很小，孔隙边界最终可以达到较高的塌缩速度。因此，在孔隙闭合阶段必须考虑点火的流体动力学机理；而对细颗粒样品，熔化则强烈地降低了点火感度。
This article explores the visco-plastic collapse mechanism of hot spots in porous TNT explosives. In studying the viscoplasticity of the media around the pore and the resulting heating, the melting effect was taken into account and the numerical calculation of the established model was carried out. The results show that under the condition of lower amplitude shock wave of about 3 GPa, due to the influence of melting, the melting zone temperature remains close to the melting point near the pore boundaries with different sizes, and the existence of the melting zone ensures that the heating layer has a certain depth . For large particles, due to the continuous expansion of the melting zone during the collapse of the pores, the yield strength in the melting zone is zero and the viscosity is very small. Finally, the pore boundary can reach a higher collapse speed. Therefore, the hydrodynamic mechanism of ignition must be considered during the pore closure phase, whereas for fine particle samples, melting strongly reduces the ignition sensitivity.