【摘要】 为深入研究钨合金杆式弹穿甲侵彻过程中的变形、失效模式,利用扫描电镜和有限元数值模拟,观测、分析钨合金残余弹芯头部剖面显微组织的变形演化。结果表明:穿甲侵彻过程中,钨合金弹芯头部发生剧烈的塑性变形而呈"蘑菇头"形状,钨晶粒被严重压扁,表出现良好的动态塑性。弹芯"蘑菇头"前端垂直侵彻方向1mm处产生绝热剪切带,剪切带内W颗粒和W-W界面上均有微裂纹产生,并表现出溶化现象。数值模拟表明,钨合金在侵彻过程中"蘑菇头"不断形成和脱落,弹芯因此发生销蚀而逐渐变短。弹芯"蘑菇头"处材料剧烈变形如同塑性流动,变形局部化主要出现在"蘑菇头"两侧边缘或前端垂直于侵彻方向处。更多还原

【Abstract】 The purpose of the present work is to investigate the deformation failure behavior of tungsten alloy long rob penetrating into armor target by metallographic analysis and numerical simulation. Microstructure evolution of the residual projectile was studied using SEM and OM. The results show that mushroom-like-head of penetrator is formed during penetration due to severe plastic deformation, and W grains in the mushroom are elongated heavily. An adiabatic shear band is observed perpendicular to the penetration direction in the front mushroom about 1 mm, in which W grains seem dissolving due to local temperature rise, and micro-cracks are developed both in W grains and W-W interface. Numerical simulation shows that the mushroom forms and falls off continuously during penetrating, so the long rob becomes shorter for the erosion. Severe plastic deformation in the mushroom is similar to plastic flow, and the deformation localization occurs mainly upon the both sides or the front of the mushroom.更多还原