热加工对管线用低碳钢性能的影响

通过热模拟实验，研究了一种管线钢相变组织的形成规律，在此基础上，进行两阶段多道次控轧和在适度冷却速度下控冷的控制热加工实验，分析了工艺参数对钢的组织结构和力学性能的影响。结果表明，开轧温度、终轧温度、终冷温度和冷却速度对管线钢的力学性能有强烈的影响。通过优化工艺，获得了以针状铁素体为主的混合组织，针状铁素体的含量越多，材料的力学性能越好。

EFFECT OF THERMOMECHANICAL CONTROL PROCESS ON MECHANICAL PROPERTY OF A LOW CARBON STEEL FOR LINE PIPE

The transformation production for a commercial pipeline steel was investigated by hot simulation test in this paper. Based on the investigation results, the schedule with a two stage multi-pass controlled rolling and moderate cooling rate was applied to hot rolling experiments and effects of the technological parameters on microstructure and mechanical property were analyzed. The experimental results show that mechanical property of the steel is strongly affected by technical parameters of thermo-mechanical control process(TMCP) such as the start rolling temperature, the finish rolling temperature, the finish cooling temperature and the cooling rate. The acicular ferrite dominated mixed microstructure can be obtained by the improved TMCP, and the more the acicular ferrite in the mixed microstructure, the higher the mechanical property of the steel.