核用SA508-3钢特厚板焊后热处理有限元分析

为了得到SA508-3钢特厚板焊接残余应力分布及焊后热处理对残余应力分布的影响,利用有限元方法对焊接及焊后热处理进行了模拟计算,计算结果表明:焊后热处理对试板焊接应力分布趋势影响较小,但焊后热处理可以大大减小接头应力数值,其中,纵向应力最大减小幅度为72%,横向应力最大减小幅度为70%;焊接接头存在应力分布准稳定区,且接头内部残余应力水平最小,其次为接头上表面,接头下表面应力水平最大;通过残余应力测定试验与模拟结果比对,两者结果吻合度很高,说明计算模型及计算方法可靠,可以指导实际SA508-3钢特厚板焊后热处理生产.

Finite element analysis on post-weld heat treatment of heavy-section SA508-3 steel plate for nuclear pressure vessel

In order to investigate the distribution of welding residual stress in heavy-section SA508-3 steel welded joint and the effect of post-weld heat treatment (PWHT) on distribution of residual stress, the welding and PWHT process was numerically simulated by using finite element method. The simulated results show that PWHT had little effect on the distribution of welding residual stress, but PWHT could significantly reduce the welding residual stress. The maximum amplitude of longitudinal stress decreased by 72%, and the maximum amplitude of transverse stress reduced by 70%. Quasi-stable stress region distributed in the welded joint. The residual stress inside the welded joint was the smallest, followed by that on the upper surface, and the residual stress on the bottom surface of welded joint was the greatest. The simulated residual stress agreed well with the experimental results, indicating that the calculation model and method are reliable and can guide the practical PWHT of SA508-3 steel plates.