中文摘要：

T91钢属于马氏体不锈钢,其焊接性能较差,焊接接头易脆化,焊接时容易产生冷裂纹和再热裂纹。基于ANSYS软件平台,应用移动高斯热源结合单元生死技术方法,对超临界锅炉用小管径T91钢的焊接残余应力进行数值模拟,分析了焊后残余应力的分布规律,讨论了焊前预热温度以及焊后热处理工艺对焊接残余应力的影响。模拟结果表明,焊后残余应力集中在T91钢焊缝区与热影响区,最大等效应力值超过了材料屈服应力值;提高焊前预热温度可以降低Mises等效残余应力值,但应力值仍然较大;进行焊后热处理可以明显改善焊接残余应力的分布,最大应力数值下降60%~70%。

英文摘要：

T91 steel is martensite stainless steel, the welding performance of T91 steel is poor, easy to produce cold cracking and reheat cracking when welding, and the welded joints is easy to brittle. Applications of Gaussian heat source binding element birth and death to simulation of supercritical boiler steel T91 welding residual stress based on the ANSYS software platform, analysis of the distribution of welding residual stress field and discussed the preheating temperature and the post-weld heat treatment press for welding residual stress. The simulation results show that the welding residual stress concentration in the weld zone and the heat affected zone, the maximum equivalent stress exceeds the yield stress value, and preheating temperature increase can reduce the Mises equivalent residual stress,but stress is still large, and post-weld heat treatment can significantly improve the distribution of welding residual stress, the maximum stress value decreased 60% to 70%.