冷轧变形量对高氮奥氏体不锈钢Mnl7Crl9N0.6组织和性能的影响

对感应炉-电渣重熔冶炼的节镍型高氮奥氏体不锈钢Mn17Cr19N0.6的3mm热轧板进行变形量10%～60%的冷轧及拉伸实验。结合金相组织观察及XRD物相分析,研究高氮奥氏体不锈钢冷变形过程中微观组织变化规律,得出结论:在冷轧过程中,随着变形量的增加,实验钢中晶粒的形状由块状到压扁拉长状,滑移从单滑移为主到交滑移,孪晶最终被分割破碎。实验钢在不同冷轧变形量后的组织均为单一的奥氏体相,并没有出现其他相,实验钢在冷变形过程中没有发生马氏体转变,因此,实验钢在冷轧过程中没有通过相变强化,以形变强化为主,抗拉强度从冷轧变形量为10%时的1045 MPa升高至变形量为60%时的1880MPa,因此通过冷变形可以制备出不同强度级别且组织为单一奥氏体的特种材料。

Effect of Cold Rolling Deformation on Structure and Property of High Nitrogen Austenitic Stainless Steel Mnl7Crl9N0.6

The cold rolling with 10% ~60% deformation and tensile tests of 3 mm hot rolled plate of saving in nickel high nitrogen austenitic stainless steel Mnl7Crl9N0.6 produced by induction furnace-electroslag remelting are carried out. The microstructure changes in the cold deformation process of high nitrogen austenitic stainless steel are studied by metallographic observation and XRD phase analysis. It is concluded that in the process of cold rolling,with the increase of the deformation ,the shape of the grain in the test steel is from lump to flat elongate, and the slip from single slip to cross slip, and the twinning band will eventually be cut and broken. The microstructure of the test steels with different cold rolling deformation is single austenite phase, and there is no other phase. There is no martensitic transformation in the cold deformation process. Therefore, no phase transformation strengthening occurred during cold rolling of test steel, and the deformation strengthening is main in the cold rolling process, the tensile strength of the test steel increases from 1045 MPa by 10% deformation to 1880 MPa by 60% deformation. Therefore, special materials with different strength levels and single austenite structure can be prepared by cold deformation.