轧制工艺对海洋工程结构用API2W-50钢组织与性能的影响

Effect of rolling process on microstructure and performance of steel API2W-50 in marine engineering structure

研究了轧制工艺对海洋工程结构用API2W-50钢组织与性能的影响。结果表明：采用控轧控冷工艺,在1000℃以上和950℃以下分两阶段轧制,终轧温度控制在820℃,轧后水冷至620℃,API2W-50钢的抗拉强度达到540 MPa,伸长率为27%,-40℃纵向冲击韧性可达到279 J,-40℃横向冲击韧性达到215 J,钢板综合力学性能最佳;得到钢组织为贝氏体＋铁素体＋珠光体,晶粒均匀细小,综合力学性能达到研制目标,具备工业性试制条件。

The effect of rolling process on the microstructure and performance of steel API2W-50 in marine engineering structure was studied. The results show that the rolling process of thermo-mechanical control processing(TMCP） is divided into two stages,above 1000 ℃and below 950 ℃. The final rolling temperature is controlled at 820 ℃ and then decreases to 620 ℃ by water-cooling after rolling. After TMCP,the tensile strength of steel API2W-50 reaches 540 MPa,the elongation is 27%,the longitudinal impact toughness at -40 ℃reaches 279 J,and the horizontal impact toughness at -40 ℃ reaches 215 J,in which the comprehensive mechanical property of steel sheet is the best. Moreover,the microstructure of steel is a mixture of bainite,ferrite and pearlite,and the grain size is uniform and small.Thus,the comprehensive mechanical property reaches the goal of development,which has the industrial trial production conditions.