表面欠陥を有するクラッド鋼の破壊強度

抄録

Fracture performance of explosive clad steel composed of SUS304 stainless steel and HT80 high strength steel is investigated. To clarify the effects of composite structures and metallurgical properties on the fracture strength and fracture strain, tensile tests are carried out by using homogeneous and heterogeneous specimens which are extracted from the clad plate and have artificial surface flaws.
The critical value of stress for the macroscopic unstable fracture initiation of the heterogeneous specimen with surface flaw in SUS304 steel is larger than that of the homogeneous SUS304 steel specimen over all temperature range, and also larger than that of the homogeneous HT80 steel specimen at very low temperature. The fracture strain of the heterogeneous specimen with surface flaw in SUS304 steel lies between that of the homogeneous SUS304 steel specimen and that of the homogeneous HT80 steel specimen over all temperature range. The critical crack mouth opening displacement of the heterogeneous specimen with surface flaw in SUS304 steel is lower than that of the homogeneous SUS304 steel specimen.