重庆大学 航空航天学院
V252???????
1.College of Aerospace Engineering,Chongqing University,Chongqing,400044
对Ti60合金试件在550℃高温环境下开展疲劳-蠕变交互试验,在疲劳应力?max=450MPa、应力比R=0.1的试验条件下,研究不同蠕变应力对钛合金疲劳蠕变行为的影响,并根据试验数据基于Norton模型提出一种能在样本有限的情况下,仅通过短时间的试验来预测较长时间的蠕变应力门槛值的预测模型。将该模型预测结果与最大轴向应力法计算结果进行对比,并将其与升降法所得试验结果进行了对比,相对误差均在2%以内,结果表明该预测模型能较为准确地预测疲劳蠕变试验条件下蠕变应力门槛值。
Fatigue-creep interaction test was carried out on Ti60 alloy specimen at 550℃. Under the test conditions of fatigue stress ?max=450MPa and stress ratio R=0.1, the influence of different creep stress on fatigue-creep behavior of titanium alloy was studied. According to the test data and based on the Norton model, a new method was proposed which can be used to improve the fatigue-creep behavior of titanium alloy with limited samples. A prediction model that predicts the threshold value of creep stress over a longer period of time only through a short period of testing. The prediction results of this model are compared with those of the maximum axial stress method and those of the lifting method. The relative error is less than 2%. The results show that the prediction model can accurately predict the creep stress threshold under the fatigue-creep test conditions.
