温变形0Cr14Mn21NiN奥氏体不锈钢的组织性能

Microstructure and properties of warm deformed 0Cr14Mn21NiN austenitic stainless steel

采用Thermal-Calc热力学计算软件对0Cr14Mn21NiN奥氏体不锈钢Cr含量进行了优化设计,探究合金成分与温变形工艺对试验钢磁导率、力学性能、耐蚀性能的影响。结果表明:试验钢磁导率随钢中Ni当量/Cr当量值的升高而降低,随析出相含量的升高而升高。在变形温度为900~1000℃时,试验钢的力学性略优于P530钢。当变形温度降低为600℃,变形量为20%时,试验钢屈服强度为1043.7 MPa,冲击吸收能量为50 J,硬度为375.36 HBW,明显优于P530钢。晶间腐蚀结果表明,Cr含量较高的试验钢没有发生晶间腐蚀,Cr含量较低的试验钢在变形温度为600℃,900℃时,发生了明显的晶间腐蚀,试样表面可以观察到明显的晶间腐蚀裂纹。综合磁导率、力学性能、耐晶间腐蚀性能,确定试验钢Cr含量为16%,温锻工艺为600℃,变形量为20%时,试验钢具备较高强度的同时还具有良好的韧性,不会发生晶间腐蚀,磁导率为1.006。

The Cr content of 0Cr14Mn21NiN austenitic stainless steel was optimized by Thermal-Calc thermodynamic calculation software.The effects of alloy composition and warm deformation process on magnetic permeability,mechanical properties and corrosion resistance of the tested steel were investigated.The results show that the magnetic permeability of the tested steel decreases with the increase of Nieq/Creq value,and increases with the increase of precipitated phase content.When the deformation temperature is 900-1000℃,the mechanical properties of the tested steel are slightly better than those of P530 steel.When the deformation temperature is reduced to 600℃and the deformation is 20%,the yield strength of the tested steel is 1043.7 MPa,the impact absorbed energy is 50 J,and the hardness is 375.36 HBW,which is obviously better than those of P530 steel.The intergranular corrosion results show that there is no intergranular corrosion in the tested steel with higher Cr content.The tested steel with lower Cr content has obvious intergranular corrosion at 600℃and 900℃deformation temperature,and obvious intergranular corrosion cracks are observed on the surface.Considering magnetic permeability,mechanical properties,and resistance to intergranular corrosion,the Cr content of the tested steel is determined to be 16%,the warm forging process is at 600℃,and the deformation is 20%,by which the tested steel has high yield strength and good toughness,has no intergranular corrosion,and its magnetic permeability is 1.006.