垂直侵彻钢靶过程中钨合金壳体破坏机理研究

Failure Behavior of Tungsten Alloy Shells Normal Penetrating Steel Targets

进行了钨合金壳体垂直侵彻45钢靶板的实验,成功地获得钨合金壳体侵彻钢靶板时变形破坏演变的完整过程。通过对回收的钨合金壳体微组织结构的观察与分析,发现钨合金壳体的主要破坏机制是危险截面区域形成绝热剪切带;其次,内腔前端区域发生粘结相撕裂。建立了壳体侵彻过程危险截面区域失效演变的3个阶段:绝热剪切带的形成、带内微裂纹的萌生和剪切裂纹的扩展。材料的失效方式与壳体存在应力集中区域密切相关,只有在壳体的结构设计中尽可能降低局部的应力集中系数,钨合金材料才能既可以发挥优异的侵彻性能,又可以保证侵彻过程完整性的要求,从而实现工程应用和军事应用。

Normal penetration of tungsten allo y shells into steel targets was perfo rmed and the total deformation and fr acture history of the shells were successfully obtained.The mic rostructure of received shells was e xamined and analyzed,revealing that the formation of adiabatic shear band at critical section is the mainl y failure behavior of tungsten alloy shell,and matrix rupture at the tip o f internal hollow also results in the damage of the shell.Furthermore,th e failure process of critical sectio n is divided into three steps,i.e.th e formation of adiabatic shear bands,the appearance of micro-cracks in the bands and the expansion of sh ear cracks.In additional,the failu res of tungsten alloy shells start at geometrical stress concentratio n zone in the all received shells,so o nly if the local stress concentratio n coefficients are markedly decreased by shell geometrical design,the tungsten alloy shells can be able to play an important role in several applications,including military engi-neering.