复合加载下锆-4合金的应力响应特征

STRESS RESPONSE OF ZIRCALLOY 4 UNDER BIAXIAL LOADING

研究了Ｚｒ－４在双向拉－拉复合加载过程中，沿不同非比例加载路径下，材料单调和循环变形行为。结果表明：锆－４合金在非比例复合加载过程中，加载路径的突然变化将引起应力矢量较应变增量矢量滞后，滞迟角及其随转折后路径长度的变化率与转折角的大小有关。宏观应力响应测试结果表明：应变路径突然转折后，材料表现出瞬时软化特征。随着塑性变形增加，则又表现为硬化特征。变形软化和重新强化的程度及其变化率与转折角大小、转折时的路径长度及转折方向有关。这一结果表明变形历史以及应变分量间的耦合效应对宏观响应的影响是不容忽视的。

It is studied that plastic deformation behavior of zircalloy 4 under biaxial cyclic loading along different loading paths The result shows that the stress vector is not coaxial with the strain increment vector after the turning point of a strain path for all specimen of zircaloy 4 The delay angle strongly depends on the variations or nonproportionality.The equivalent stress suddenly drops then increases,firstly softening and subsequently hardening degrees are related to the turning angle values,the path length and turning direction Therefore,the influences of the deformation history and the coupled effects among strain components on the response can not be neglected