50Mn18Cr4V高锰无磁钢板的组织与性能

Microstructure and properties of 50Mn18Cr4V non-magnetic high manganese steel plate

实验观察了50Mn18Cr4V高锰无磁钢板材热轧和热处理后的微观组织,并测试了其力学性能和磁导率。结果表明:轧制板材厚度≤4.5mm时,由于终轧温度较低,钢中VC第二相的应变诱导析出对50Mn18Cr4V钢发生动态再结晶的抑制作用更加明显,导致热轧板组织全部为变形的奥氏体,需要通过后续热处理改善综合性能。固溶处理过程以较小的速度冷却,有助于减少钢中马氏体的生成量。经过650℃时效处理5h后,实验钢的屈服强度为604 MPa,抗拉强度为1 020 MPa,断后伸长率为40%,相对磁导率为1.002,具有良好的力学性能与较低的磁导率。

The microstructure of 50Mnl8Cr4V non-magnetic steel plate after hot rolling and heat treatment was observed and then the mechanical properties and permeability of the corresponding samples were measured. The results show that when the thick- ness of hot rolled plate is less than 4. 5 ram, the strain induced precipitation of VC causes more remarkable inhibition of dynamic recrystallization in the 50Mn18Cr4V steel due to low finishing temperature. As the finishing temperature and thickness are re duced, the microstructure of hot rolled plate is all deformed austenite grains and subsequent heat treatment is needed in order to obtain a good combination of properties. The production of martensite is reduced with decreasing cooling rate during solution treatment. After aging treatment at 650 ℃ for 5 h, the yield strength, tensile strength, and relative permeability of the steel are 604 MPa, 1 020 MPa, and 1. 002, respectively, which shows good mechanical properties and low permeability.