节镍型奥氏体不锈钢14.0Cr-1.1Ni-9.2Mn-0.30Cu组织及性能

Microstructure and Properties of Low-nickel Austenitic Stainless Steel 14.0Cr-1.1Ni-9.2Mn-0.30Cu

在13.36Cr-1.12Ni-11.2Mn节镍型奥氏体不锈钢基础上降Mn加Cu,优化开发14.0Cr-1.1Ni-9.2Mn-0.30Cu不锈钢,并研究不同化学成分奥氏体不锈钢固溶处理、冷轧退火后的金相组织、显微织构、力学性能及成形性能,分析了奥氏体稳定性和冷轧形变诱导马氏体相变的控制规律。结果表明:14.0Cr-1.1Ni-9.2Mn-0.30Cu与13.36Cr-1.12Ni-11.2Mn不锈钢力学性能相当,固溶处理、冷轧退火后奥氏体组织再结晶充分,冷轧平均晶粒尺寸分别为12.6μm、14.0μm,显微织构为铜织构{112}<111>;14.00Cr-1.1Ni-9.2Mn-0.30Cu不锈钢的杯突值和极限拉深比分别为16.15和0.46,优于13.36Cr-1.12Ni-11.2Mn不锈钢;14.0Cr-1.1Ni-9.2Mn-0.30Cu与13.36Cr-1.12Ni-11.2Mn钢Md30/50分别为87.02℃和83.55℃,Md30/50高,则奥氏体稳定性差,形变诱导马氏体量和冷轧变形抗力大,退火后硬度高。通过将冷轧退火工艺速度由10 m/min降低至9 m/min,可改善退火后钢的硬度。

14.0 Cr-1.1 Ni-9.2 Mn-0.30 Cu stainless steel was developed on the basis of 13.36 Cr-1.12 Ni-11.2 Mn low-nickel austenitic stainless steel,and the metallographic structure,microstructure,mechanical properties and forming properties of austenitic stainless steel with different chemical compositions after solution treatment and cold-rolled annealing are studied,as well as the control laws of austenite stability and cold rolling deformation induced martensitic transformation were analyzed.The results show that the mechanical properties of 14.0 Cr-1.1 Ni-9.2 Mn-0.30 Cu and that of 13.36 Cr-1.12 Ni-11.2 Mn stainless steel are equivalent,the austenitic structure is fully recrystallized after solution treatment and cold-rolled annealing,the average grain size of cold rolling is 12.6μm and 14.0μm respectively,and the microstructure is copper texture{112}<111>;the IE(bulge test impression endurance value)and LDR(Limited Drawing Ratio)of 14.0 Cr-1.1 Ni-9.2 Mn-0.30 Cu stainless steel are 16.15 and 0.46 respectively,which are better than those of 13.36 Cr-11.2 Mn stainless steel,and the Md30/50 temperature of 14.0 Cr-1.1 Ni-9.2 Mn-0.30 Cu and 13.36 Cr-1.12 Ni-11.2 Mn stainless steel are 87.02℃and 83.55℃respectively,as Md30/50 high,the austente stability poor,the deformation introducing martensite volume and cold-rolled deformation resistance increasing,the hardness of annealed steel high.But the hardness after annealing can be improved by reducing the speed of cold-rolled annealing process from 10 m/min to 9 m/min.