摘要
将60mm厚控轧控冷态的E690海洋平台钢板分别进行730、760、790、820、850、880、910℃的淬火处理,使用扫描电镜和透射电镜对淬火后钢板的组织进行观察和分析。结果表明:730℃加热保温,奥氏体首先在粒状贝氏体晶界处形核,细小奥氏体成独立的岛状沿晶界分布;760℃进行保温,奥氏体在沿晶界生长过程中发生合并;加热温度进一步升高到790℃,奥氏体不仅在原粒状贝氏体晶界成网状分布,晶内也开始有细小奥氏体生成;820℃及以上温度保温,奥氏体晶粒尺寸在1～3μm。未奥氏体化的粒状贝氏体在加热过程中发生回复和再结晶,晶内的M/A岛不断的分解并逐渐扩散消失。
TMCP 60 mm thickness E690 offshore plateform steel plates were quenched at 730, 760, 790, 820, 850, 880 and 910℃, respectively. The microstructure was investigated by scanning electron microscope and transmission electron microscope. The results show that when heat preserved at 730~C, the austenite generates at the boundary of granular bainite firstly,tiny austenite islands distributes along with the grain boundary; heat preserved at 7600C, the austenite islands along with grain boundary becomes merging, heat preserved at 790~C, austenite looks like net along with grain boundary and also generates at inner grain meanwhile; with the increase of quenching temperature to 820 ~C, the austenite size is in 1-3 Ixm. The granular bainite which not transformed into austenite produces relaxation and recrystallization. The martensite/austenite islands inner granular bainite resolves continually and disappears during heating process.
出处
《热加工工艺》
CSCD
北大核心
2012年第24期113-116,120,共5页
Hot Working Technology
关键词
海洋平台
低碳贝氏体
热处理
offshore plateform
low carbon bainitic
heat treatment
