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本文研究了两种方式载荷循环（矩形波和锯齿波）对走向凝固镍基高温合金DZ17G高温蠕变行为的影响结果表明，与恒载荷静态蠕变相比，载荷循环并不影响蠕变塑性，但降低了蠕变寿命，蠕变寿命的降低程度近似与载荷循环次数成正比，且短形波载荷循环比锯齿波载荷循环效果更为明显提出载荷循环导致蠕变寿命的降低与载荷变化引起的滞弹性效应无关，而是蠕变变形加速的结果．在载荷降低时，蠕变阻力的松弛导致在随后加载期间，试样以比相应静态蠕变变形速率更快的速率变形，发生了循环软化，每一次载荷循环产生的循环软化的积累，导致蠕变变形速率不断提高，最终降低了DZ17G合金的高温蠕变寿命
The effects of two kinds of loading cycles (rectangular wave and sawtooth wave) on the creep behavior at high temperature of the solidified Ni-based superalloy DZ17G are studied. The results show that the loading cycle does not affect the creep ductility, But reduce the creep life, the degree of reduction of creep life is approximately proportional to the number of load cycles, and the short-wave load cycle is more obvious than the sawtooth wave load cycle effect. It is proposed that the load cycle leads to the decrease of creep life and the change of load Anelastic effect has nothing to do, but the result of accelerated creep deformation. As the load decreases, the relaxation of creep resistance causes the specimen to deform more rapidly than the corresponding static creep deformation rate during subsequent loading, undergoes cyclic softening, the cyclic softening build-up resulting from each loading cycle, Variable deformation rate continues to increase, eventually reducing the high temperature creep life of DZ17G alloy