High Temperature Plasticity of Continuous Casting Slabs for K60 and X80 Pipeline Steels

The high temperature plasticities of continuous casting slabs for K60 and X80 pipeline steels were studied by Gleeble 1500 thermomechanical simulator in the temperature range 1 350℃ to 650℃ at a low strain rate of 1.0×10-3 s-1.The results show that the embrittlement region Ⅰ of the two steel slabs was between melting point and 1 300℃.In the high temperature range(between 1 300℃ and 900℃),the plasticities of both the steels were excellent and there was no evident embrittlement.The embrittlement temperature region III was between 900℃ and 700℃,Which was consist of single γ phase region and γ+α phase region.