异种金属焊接接头弹塑性裂纹扩展探究

Research of elastic-plastic crack propagation for dissimilar metal welded joint

针对含缺陷核电关键构件的裂纹扩展情况,以核电一回路安全端异种金属焊接接头为研究对象,建立了含预制裂纹的"三明治"材料模型,并基于扩展有限元法对焊接接头不同位置的裂纹扩展情况进行了详细对比分析。结果表明,裂纹扩展过程可分为3个阶段,且总是偏向向屈服极限较小的一侧扩展。研究结果可为含裂纹核电关键构件的剩余使用寿命评估提供依据,为后续研究及工程应用提供参考。

For the crack propagation in the defected key component of nuclear power,a ＂sandwich＂material model with preset cracks inclusive was established by choosing the dissimilar metal welded joint of the primary circuit safety end as the research target.And the crack propagation at different positions of the welded joint was systematically analyzed and compared by XFEM.The results show that the crack propagation process can be divided into three stages and always tends to propagate towards the part with smaller yield limit.The research results can provide the basis for the remaining service life assessment of the key component of nuclear power with cracks,and can also provide references for future research and engineering application.