通过对圆形横截面光滑试样进行轴向应变控制的低周疲劳试验,研究了加载频率与应变比对10CrNi5Mo高强钢疲劳寿命的影响。结果表明: 在较低频率(0.05～0.1 Hz)范围内,频率对疲劳寿命的影响不明显,随着加载频率的增加(0.1～0.8 Hz),疲劳寿命显著提高,当加载频率增加到0.8 Hz时,疲劳寿命达到最大值,随着加载频率的继续增加(0.8～1.0 Hz),疲劳寿命反而有所下降; 在最大应变不变条件下, 随着应变比的增加(-1～-0.3),疲劳寿命平稳上升,当应变比增加到-0.30时,随着应变比的继续增加,材料的疲劳寿命急剧升高。研究结果为10CrNi5Mo高强钢的工程应用提供了依据。

Adopting smooth round-section specimens, through axial loading low cycle fatigue test controlled by strain mode, effect of loading frequency and strain ratio on low cycle fatigue life of 10CrNi5Mo high strength steel were investigated. The results indicated that no significant influence of loading frequency on fatigue life was observed for the frequency in the range of 0.05-0.1 Hz, however, with loading frequency increasing to 0.8 Hz, fatigue life increased and then fatigue life dropped for increasing loading frequency to 1.0 Hz. When the maximum strain being constant, with strain ratio increasing (from -1 to -0.3), fatigue life of the steel increased gradually and when stain ratio arrived at -0.3, the fatigue life improved markedly with strain ratio further increasing, which would provide reference for engineering application of 10CrNi5Mo high strength steel.