T91/TP347H异种钢焊接接头蠕变行为分析及寿命预测

Creep Behavior Analysis and Life Prediction of T91/TP347H Dissimilar Steel Welded Joint

在恒定温度、不同应力下进行了T91/TP347H异种钢焊接接头的高温蠕变实验。采用修正的θ投影模型来描述T91/TP347H异种钢焊接接头的蠕变性能,结合蠕变断裂经验公式推导出最小蠕变速率的解析表达式,并提出了新的蠕变寿命预测模型。结果表明:采用修正的θ投影模型得到的蠕变曲线拟合值与实验值吻合良好,可准确地表达出蠕变曲线3个阶段的特性;所提出的蠕变寿命预测模型的预测误差在5%之内,预测精度较好。

High temperature creep tests of T91/TP347 H dissimilar steel welded joints were carried out under constant temperature and different stresses.The modifiedθprojection model was used to describe the creep behavior of T91/TP347 H dissimilar steel welded joints.Combined with the empirical formula of creep fracture,the analytical expression of minimum creep rate was derived,furthermore,a new creep life prediction model was proposed.Results show that the fitting curve obtained by modifiedθprojection model is in good agreement with experimental results,which could accurately express the three-stage characteristics of creep curve.Prediction error of the proposed creep life prediction model is within 5%,which shows good prediction accuracy.