Microstructure and mechanical properties of hot rolled stainless steel clad plate by heat treatment

Series of stainless steel clad plates were heat treated at the quenching temperatures ranging from 900 degrees C to 1150 degrees C for holding time of 6min and 60min, respectively. It was observed that the ferrite and pearlite phases in the hot-rolled carbon steel substrate changed into lath martensite and needle-like ferrite through quenching treatment. The carburized layer thickness was gradually decreased till disappeared, and the interfacial shear strength was firstly increased and then decreased with the increasing quenching temperature, which was attributed to the sufficient alloy element diffusion and matrix softening at the high quenching temperature. At the quenching time of 6min, the shear fracture zone transmitted from the interface into the decarburized layer with the increasing quenching temperature, and the severe interfacial delamination cracks all existed at the clad interface. However, the main shear cracks were all presented at the decarburized layer for the quenching time of 60min, and there were no interfacial delamination cracks in the tensile samples, revealing that strong interface can be obtained by prolonging quenching time. The tensile behavior and fracture characteristics showed the ductile-brittle transition with the increasing quenching temperature.