基于短时应力松弛试验的蠕变行为预测方法

分析了现有蠕变加速试验方法，特别是基于超出弹性应变初应变的松弛试验的蠕变设计方法的固有缺陷。进行了高温材料1Cr10NiMoW2VNbN的多组短时应力松弛试验；根据松弛与蠕变的关系，综合利用数值计算方法和图解法获得材料稳态蠕变应变速率，以进行蠕变强度设计，形成一套完整的基于应力松弛的蠕变加速试验方法。结果发现，基于短时松弛试验转换得到的蠕变数据与常规蠕变试验结果吻合较好，表明这一方法可用于高温构件的蠕变行为预测和强度设计。

Creep Performance Prediction Method Through Short-term Stress Relaxation Tests

It was analyzed that the intrinsic limitation of present accelerated creep test methods, especially creep design method through stress relaxation tests with an exceeding pre-strain to elastic-strain. A set of short term stress relaxation tests of 1Cr10NiMoW2VNbN steel were carried out. Based on the relationship between stress relaxation and creep, the creep strain rate corresponding to the steady state creep stage were achieved through the stress relaxation test by using numerical analysis and a cross-plotting approach. And then, the second stage creep curves were constructed for high temperature strength design. An integrated accelerated creep test methodology through stress relaxation tests was therefore established. Results of creep tests indicate that the developed method can lead to a good agreement with the experimental data and thus is recommended in the creep performance prediction and strength design of high temperature components.