【摘要】 采用轴向应变控制方法,结合4种试验方案,在MTS809拉扭复合疲劳试验机上对18根试件进行拉压低周疲劳试验,对比研究引伸计刀口对低周疲劳失效位置、循环应力响应特征曲线、塑性应变能密度的影响以及消除引伸计刀口影响的最佳方案。结果表明:引伸计刀口对低周疲劳数据的有效性的确存在较大的影响,对试件存在一定的损伤。在试件与刀口接触处贴上透明胶是一种避免引伸计刀口损伤,提高试件有效利用率,并节约资源的有效办法。更多还原

【Abstract】 With four different methods,a total of 18 low cycle fatigue(LCF) experiments under uniaxial strain control were carried out on a MTS 809 servo-hydraulic material testing machine.The sites of LCF fatigue failure of specimens,the cyclic stress response characteristics and the plastic strain energy density were investigated.The knife edges had considerable effects on the results of the LCF and injury to the specimens.By comparing all the experimental results,an effective method has been proposed to avoid the injury to the knife edges.Using this method,the availability of specimens could be enhanced and the resource could be saved.更多还原