304不锈钢在单轴应变棘轮变形下的随动硬化实验研究

Experimental Study on Evolution of Kinematic Hardening for Stainless Steel 304 under Uni-axial Strain Ratcheting Deformation

对304不锈钢在室温下进行了单轴应变控制下的应变棘轮变形与失效以及低周疲劳试验研究,对材料在循环过程中材料的硬化行为进行了系统的揭示。在对称应变循环下,研究了不同应变幅值下弹性区尺寸和背应力演化规律；在给定工程应变幅值和循环棘轮应变增量组合的应变棘轮变形下进行了弹性区尺寸和背应力演化研究。观察到了各向同性硬化和随动硬化演化对加载历史的依赖性。

The tests of cyclic strain ratcheting and low cycle fatigue for stainless steel 304 under uni-axially cyclic strain at room temperature were conducted to systematically investigate the hardening be- havior of the material. The evolutions of elastic field size and back stress were investigated under symmetrical cyclic strain with different strain amplitudes and under the strain ratcheting cycling with combined different engineering strain amplitudes with the specific cyclic ratcheting strain increments. The dependence of the evolutions of isotropic and kinematic hardening on the loading history was observed.