12Cr 18Ni 12Ti/12Cr 1MoV异种耐热钢焊接接头蠕变数值模拟

摘要

采用有限元方法对奥氏体耐热钢(12Cr18Ni12Ti)与珠光体耐热钢(12Cr1MoV)焊接接头在温度为540℃、外加轴向拉应力为80 MPa条件下的蠕变最大主应力、von Mises 等效应力和等效蠕变应变进行了数值模拟。结果表明,焊缝/12Cr1MoV界面附近区域的最大主应力数值很高,蠕变孔洞易于在焊缝/12CR1MoV 界面区域形成。焊缝/12Cr1MoV界面附近的von Mises等效应力数值也很高,因而,孔洞易于扩张。蠕变变形主要发生在12Cr1MoV母材一侧,最大等效蠕变应变位于距焊缝/12Cr1MoV 界面约5.3mm,界面附近存在蠕变拘束。焊缝/12Cr1MoV界面为接头的薄弱环节。%Finite element is used for numerical simulation on the maximum principal stress,von Mises equivalent stress and e-quivalent creep stress in dissimilar welded joint between austenitic heat-resistant steel (12Cr18Ni12Ti )and pearlitic heat-re-sistant steel (12Cr1MoV)under conditions of 540℃ and applied stress being 80 MPa. The results indicate that the maximum principal stress is quite high in the vicinity of weld 12Cr1MoV interface and creep cavities are easy to form in the weld 12Cr1MoV interface zone. The von Mises equivalent stress in the vicinity of weld 12Cr1MoV interface is also high and creep cavities are easy to expand as well. Creep deformation occurs at one side of 12Cr1MoV steel,the maximum equivalent creep strain is 5.3 mm from the weld 12Cr1MoV interface and there is creep constrain in the weld 12Cr1MoV interface. Thus it can be seen that weld 12Cr1MoV interface is the weakest part of 12Cr18Ni12Ti/12Cr1MoV welded joint.