Mn含量对Mn-Al系TRIP钢组织和力学性能的影响

Effect of Mn Content on Microstructure and Mechanical Properties of Mn-Al TRIP Steel

利用两相区退火和低温回火的热处理工艺,研究Mn含量分别为2%和10%的2种Mn-Al系TRIP钢组织和力学性能,并与热轧态组织与性能进行比较。研究结果表明:热轧态1号试验钢成分以铁素体组织为主,2号试验钢为铁素体+奥氏体双相组织,随着Mn含量的增多,奥氏体含量增多。10%Mn的TRIP钢整体力学性能比2%Mn的TRIP钢差。经过800℃×30min+300℃×10min热处理工艺,1号钢和2号钢中都有残余奥氏体生成。在进行拉伸实验时,这些残奥大多数都会转变为马氏体,使得TRIP钢强韧性整体提高。

The microstructure and mechanical properties of two different manganese content Mn-Al TRIP steels were studied by two-phase annealing and low-temperature tempering heat treatment.They were compared with hot rolled microstructure and properties.The experimental results show that the composition of the experimental steel in hot-rolled No.1is mainly composed of ferrite structure,and the experimental steel No.2is a ferrite+austenite two-phase structure.With the increase of manganese content, the austenite content increases.The overall mechanical properties of No.2experimental steel is lower than that of No.1steel.After 800°C×30min+300°C×10min heat treatment process,residual austenite formation in both No.1steel and No.2 steel.In the tensile deformation experiment,most of these retained austenite was transformed into martensite ,which made the steel toughness overall improvement.