304不锈钢的高温单轴应变循环与棘轮行为

ON CYCLIC STRAIN BEHMIOR AND RATCHETTING OF 304 STAINLESS STEEL UNDER UNIAXIAL LOADING AT HIGH TEMPERATURE

对304不锈钢分别进行了高温单轴应变控制和应力控制下的系统循环试验揭示和分析了循环应变幅值、应变幅值历史以及温度历史对循环特性的影响以及应力幅值、平均应力及其历史对循环蠕变（棘轮效应）的影响研究表明，无论单轴应变循环特性还是非对称单轴应力下的棘轮效应不但依赖于当前温度和加载状态。

An experimental study was carried out of the cyclic properties of 304 stainless steel subjected to uniaxial strain and stress at high temperature. The effects of cyclic strain amplitude, temperature and their histories on the cyclic deformation behavior of 304 stainless steel were investigated, and the influences of stress amplitude, mean stress, temperature and their histories on the cyclic creep (i.e., ratchetting)were also analyzed. It is shown that either uniaxial cyclic property under cyclic strain or ratchetting under asymmetric uniaxial cyclic stress depends not only on the current temperature and loading state, but also on the previous loading history. Some significant results were obtained.