| With the rapid development of automotive industry in China, problems such as automotive weight reduction, fuel saving, car safety and environment protection have attracted more and more people's attention. As one of advanced high strength steel, dual phase (DP) steel is widely used in producing cars nowadays and in the coming future. Cold rolled DP steel has high strength, low yield ratio, high work hardening index and bake hardening ability, has no yield elongation and room temperature aging effect. 780MPa class DP steel has been commercial produced in many famous steel factories. Baosteel, the main supplier of automobile steel sheets in China, has invested a lot in high strength DP steel sheets study and also made much progress.In this paper, cooling ability of continuous annealing heat treatment producing line in Baosteel has been investigated, and the technology of water quenching and tempering processes has also been studied. 1000MPa... |
