热挤压钨重合金纤维方向对绝热剪切特性的影响规律及机理研究

Effect Mechanism of Fibre Orientation on the Adiabatic Shear of as-Extruded WHA

摘要:

对烧结态93W-4.5Ni-2.1Fe-0.35Co合金进行热挤压，获得纤维状微观组织，沿与挤压轴向0o、45o和90o方向取样进行动态压缩，对试验后的试样进行微观分析和绝热剪切特性分析。结果表明，热挤压钨合金的绝热剪切特性具有显著的各向异性，纤维与压缩轴角度越大，绝热剪切敏感性越高。最大剪切应力面上粘结相的分布及受力状态改变导致绝热温升变化，这是绝热剪切特性各向异性的主要原因。

Abstract:

The 93W-4.5Ni-2.1Fe-0.35Co liquid-phase sintered tungsten heavy alloy (WHA) was fabricated by hot-hydrostatic extrusion at 950 ℃ with plastic deformation ratio of 75%. The specimens for dynamic compression tests were taken from the as-extruded WHA rod along three different directions with the extruding direction. The test results show that the adiabatic shear characteristics of WHA are highly anisotropy for different fiber orientations due to the different adiabatic temperature rise in the different micro-strained condition and the distribution of matrix and fiber.