摘要
基于SYSWELD软件,模拟了P91钢激光对接焊时的温度场和焊接残余应力,并探讨了固态相变产生的体积膨胀、屈服强度变化和相变塑性对焊接残余应力的影响.数值模拟结果表明,体积膨胀和屈服强度变化对焊接残余应力的大小与分布有显著的影响;相变塑性在相变过程中有"应力松弛"效应,对焊缝和热影响区的纵向和横向残余应力的值有一定程度的影响.对比数值模拟结果与试验结果可知,采用文中建立的有限元模型计算得到的残余应力与中子法测量得到的结果基本吻合,在考虑相变塑性的情况下,计算结果与实测值吻合更好.
Based on SYSWELD code,a computational approach was developed to simulate the temperature field and residual stress distribution in a butt joint of P91 steel plates welded by laser beam. The influence of the volume change,yield strength variation and transformation induced plasticity( TRIP) due to austenite-martensite transformation on welding residual stresses was numerically investigated. The simulation results showed that both volumetric change and yield strength variation have significant influence on the distribution and magnitude of welding residual stress. The influence of TRIP seems to be inferior to the former two factors,but it can relax both the longitudinal and transverse residual stresses to some extent in the weld zone and HAZ.Comparing the simulation results with the measured data obtained from the opening literature,we can find that the longitudinal residual stresses predicted by the present numerical model generally are in good agreement with the measurements obtained by neutron diffraction technique. When TRIP is considered in the finite element model,the simulation results match the measurements better.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2015年第5期41-43,64+115,共5页
Transactions of The China Welding Institution
基金
国家自然科学基金资助项目(51275544)
中央高校基金资助项目(CDJZR12130036)
关键词
P91钢
固态相变
焊接残余应力
数值模拟
P91 steel
solid-state phase transformation
welding residual stress
numerical simulation
