微细观结构对预扭转钨合金材料绝热剪切的影响

STRUCTURAL INFLUNENCE ON THE ADIABATIC SHEARING FAILURE OF PRE TORQUED TUNGSTEN HEAVY ALLOY

在分离式霍普金森压杆装置上对斜圆柱粉末烧结钨合金试件进行了冲击实验，由于斜圆柱结构中剪切分量在冲击压缩中的持续作用，实验中观察到了宏观破断现象．利用光学显微镜对试件的纵截面进行了分析，观察到了贯通钨颗粒的绝热剪切带这一变形局部化现象．观察到材料的微。

A combined compression/shear testing method was used in order to investigate the propensity of pre torqued tungsten heavy alloy containing 93% W and the Ni on Fe in a 7∶3 ratio. The combined simultaneous loading is applied by a split Hopkinson pressure bar (SHPB), which generates strain rate as high as 10 3s -1 . The cylindrical specimen has its axis inclined to the loading axis. Adiabatic shear localization has been observed in the high rate compression/shear tests; relatively narrow shear bands are formed, followed immediately by catastrophic fracture. The deformed microstructures are examined using electron microscopy and optical microscopy. Examination of the deformed microstructures supplies new insight into the deformation and failure mechanism of pre torqued tungsten heavy alloy.