W-Cu复合药型罩EFP的形成及其聚能破甲效应研究

在爆炸压实技术中，粉体中激波和稀疏波的强度及作用时间直接影响压实体的质量。为探究爆炸压实中不同因素对粉体中压力变化的影响，基于AUTODYN有限元程序，建立了爆炸压实W-Cu粉末的有限元模型，通过流固耦合算法实现炸药、盛粉管和W-Cu粉末的相互作用。建立与现有试验对应的有限元模型，模拟结果和试验结果具有较好的吻合性，验证了模型和材料参数的可靠性。通过对爆炸压实过程的数值模拟，分析了装药厚度和盛粉管厚度对爆炸压实压力的影响。结果表明，装药厚度越厚，激波压力的作用时间越长，对粉末的压实越有利；随着装药厚度的增加，作用时间的增长减缓。盛粉管厚度越厚，粉体中稀疏波的强度越低，对压实体的影响越小；但随着管厚增加，粉体中心压力将会降低，粉末的压实质量下降；故选择盛粉管厚度时，需综合考量粉体中心压力和稀疏波强度对爆炸压实体的影响。

Bubbles formation in helium ion irradiated Cu/W multilayer nanocomposites: Effects on structure and mechanical properties

In explosive compaction technology, strength and action time of shock wave and rarefaction wave in powder directly affect quality of the pressed solid. In order to investigate influence of different factors on pressure change in powder in explosive compaction, based on AUTODYN finite element program, a finite element model of explosive compaction W-Cu powder was established and interaction between explosive, powder tube, and W-Cu powder was realized through a fluid-solid coupling algorithm. The finite element model corresponding to the existing experiment was established. The simulation results were in good agreement with experiment results, which verified reliability of the model and material parameters. Through numerical simulation of explosive compaction process, influence of thickness of charge and thickness of powder tube on explosive compaction pressure was analyzed. The results revealed that the thicker the charge thickness was, the longer the shock pressure action time was, and it was more favorable to powder compaction. With the increase of charge thickness, the increase of action time slowed down. The thicker the powder tube thickness was, the lower the intensity of rarefaction wave in the powder was, and the smaller the influence on pressure entity was. However, with the increase of tube thickness, the central pressure of powder would decrease, and compaction quality of powder would decrease. Therefore, when selecting powder tube thickness, it was important to consider both center pressure of powder and intensity of rarefaction wave on explosion pressure entity.