轧后冷速对X100管线钢组织和力学性能的影响

Effect of Cooling Rate Following Rolling on Microstructure and Mechanical Properties of X100 Pipeline Steel

通过热模拟试验机、光学显微镜对X100管线钢在连续冷却转变下的显微组织进行了研究,然后对其进行热轧,研究了轧后冷速对试验钢组织和力学性能的影响。结果表明:随冷速增大,试验钢组织中依次出现多边形铁素体、粒状贝氏体和贝氏体铁素体;当轧后冷速为20～42℃·s-1时,试验钢可获得由粒状贝氏体和贝氏体铁素体组成的组织以及良好的力学性能。

The microstructure of X100 pipe steel during continuous cooling transformation was studied by thermal simulation testing and optical microscopy, and then the tested steel was hot rolled and the effects of different cooling rates following rolling on microstructure and mechanical properties of the tested steel were studied. The results show that the microstructure changed from polygonal ferrite, granular bainite to bainitic ferrite with the increase of cooling rate. The mierostrueture comprised by granular bainite and bainitic ferrite and excellent mechanical properties were obtained when the cooling rate was 20--42 ℃· s-1