Effect of fibrous orientation on dynamic mechanical properties and susceptibility to adiabatic shear band of tungsten heavy alloy fabricated through hot-hydrostatic extrusion
Effect of fibrous orientation on dynamic mechanical properties and susceptibility to adiabatic shear band of tungsten heavy alloy fabricated through hot-hydrostatic extrusion
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DOI：
10.1016/j.msea.2007.10.012
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发表时间：
2008-07-25
期刊：
影响因子：
6.4
通讯作者：
Sun Hongchan
中科院分区：
文献类型：
--
作者：
Liu Jinxu;Li Shukui;Sun Hongchan
采用950℃热-静液挤压工艺获得了塑性变形率为75%的纤维状高密度钨合金(WHAS)。系统地研究了加载方向与挤压方向成0°、45°和90°夹角的单轴动态压缩下的动态力学行为。试验结果表明，不同试件的动力性能和绝热剪切带敏感性有明显差异。在0度试件中，没有观察到局部流动。45度试件表现出轻微的局部剪切。在90度试件中，首先观察到局部ASB与纤维取向成45度角，然后破裂，这对于动能渗透应用是非常必要的。显微组织分析表明，90°试件对ASB的高敏感性是由于动态加载过程中绝热温升以及特殊的微观应变状态和纤维分布导致的应变硬化降低所致。(C)2007 Elsevier B.V.保留所有权利。
The tungsten heavy alloys (WHAs) with fibrous grains were obtained by hot-hydrostatic extrusion at 950 degrees C with plastic deformation ratio of 75%. Dynamic mechanical behaviors under uniaxial dynamic compression were systematically investigated with the angles between the loading direction and the extruding direction being 0 degrees, 45 degrees and 90 degrees. The testing results show obvious difference in dynamic behaviors and susceptibility to adiabatic shear band (ASB) for different specimens. In the 0 degrees specimens, no localized flow is observed. The 45 degrees specimens exhibit slight localized shearing. In the 90 degrees specimens, localized ASB was firstly observed at an angle of 45 degrees with respect to the fibrous orientation followed by cracking, which is greatly desirable for kinetic energy penetration applications. Microstructure analyses reveal that the high susceptibility to ASB of the 90 degrees specimens result from adiabatic temperature rising during dynamic loading and reduced strain hardening caused by the special micro-strained condition and fiber distribution. (c) 2007 Elsevier B.V. All rights reserved.