1986 Volume 29 Issue 258 Pages 4026-4030
In the pressure vessel of a reactor which is subjected to some kinds of thermal loading, the J integral for an assumed crack is evaluated using the finite element method. By considering the effect of the stainless steel cladding, the J integral is extended to the multi-phase material. First, a two dimensional crack is treated. Two cases, one a surface crack and the other an embedded one, are analyzed and the effect of the cladding on the J value is studied. It is shown that the cladding effect appears in a complicated form and it changes with the position of the crack and the cladding. Second, a athree dimensional embedded crack is analyzed. Thre three dimensional J integral is evaluated around a crescent type crack, and the result is compared with that of a two dimensional analysis. It is concluded that two dimensional modelling is enough to discuss the cladding effect in the case considered in this paper.