Simultaneously Enhancing Strength, Ductility and Corrosion Resistance of a Martensitic Stainless Steel via Substituting Carbon by Nitrogen  

作　　者：Fuyang Li Jialong Tian Huabing Li L.M.Deineko Zhouhua Jiang 

机构地区：[1]School of Metallurgy,Northeastern University,Shenyang,110819,China [2]National Metallurgical Academy of Ukraine,4,Haharina Ave.,Dnipro,49600,Ukraine

出　　处：《Acta Metallurgica Sinica(English Letters)》2023年第5期705-716,共12页金属学报（英文版）

基　　金：supported by the Fundamental Research Funds for the National Natural Science Foundation of China(No.52004059);the Program of Introducing Talents of Discipline to Universities(No.B21001);the Central Universities(No.N2125017);the Talent Project of Revitalizing Liaoning(No.XLYC1902046).

摘　　要：Two martensitic stainless steels of 2Cr12Ni6 type hardened and tempered at 773 K have been studied:the first with 0.2%carbon content and the second with partial replacement of carbon by nitrogen(C0.1N0.1)in the first steel.It is found that the partial substitution of carbon with nitrogen contributed to an increase in ductility and strength of the steel,presumably due to the formation of more dispersive carbonitrides.Meanwhile,the addition of nitrogen suppressed the precipitation of carbonitrides,so that the solid solution strengthening effect of C0.1N0.1 did not decrease significantly after tempering treatment.In addition,the partial replacement of carbon by nitrogen contributed to improved ability against pitting corrosion(PC)in chloride-containing medium(3.5%NaCl at 303 K).The higher resistance to PC of tempered nitrogen-containing steel is apparently due to the lower content of massive carbonitrides,especially the reduced aggregation at grain boundaries.This leads to a lower acidity and aggressiveness of the test solution near the sample surface due to the accumulation of NH4^(+) ammonium ions in it.As a result of nitrogen addition,exception for Cr_(23)C_(6) and VC,Cr_(2)N and(Cr,V)N type precipitates have also been found in C0.1N0.1 steel and this is consistent with the thermodynamic calculation results.In conclusion,substituting carbon by nitrogen in traditional martensitic stainless steel could realize the simultaneous improvement of multiple properties of martensitic stainless steels.This result provides a promising composition optimization route to develop novel martensitic stainless steels.

关 键 词：Martensitic stainless steel Strength and ductility PITTING CARBONITRIDES 

分 类 号：TG142.71[一般工业技术—材料科学与工程]