新型超级奥氏体不锈钢析出行为与力学性能  

Precipitation behavior and mechanical properties of a new-type super austenitic stainless steel

作　　者：胡华烁 张树才 禹江涛 左鹏 覃章冶 李花兵 HU Huashuo;ZHANG Shucai;YU Jiangtao;ZUO Peng;QIN Zhangye;LI Huabing(School of Metallurgy,Northeastern University,Shenyang 110819,Liaoning,China;Technology Center,Ningbo Iron and Steel Co.,Ltd.,Ningbo 315807,Zhejiang,China;Key Laboratory for Ecological Metallurgy of Multimetallic Ores(Ministry of Education),Northeastern University,Shenyang 110819,Liaoning,China)

机构地区：[1]东北大学冶金学院,辽宁沈阳110819 [2]宁波钢铁有限公司技术中心,浙江宁波315807 [3]东北大学多金属共生矿生态化冶金教育部重点实验室,辽宁沈阳110819

出　　处：《钢铁研究学报》2024年第9期1212-1220,共9页Journal of Iron and Steel Research

基　　金：国家自然科学基金资助项目(52325406,52004061);国家级大学生创新创业训练计划项目(230088)。

摘　　要：随着Ni、Mo等价格飙升,开发节约Ni、Mo型高性能不锈钢势在必行。研究基于S32654的成分,利用加压冶金和合金设计手段开发了24.5%Cr-17%Ni-5%Mn-6.3%Mo-0.7%N新型超级奥氏体不锈钢,研究了该钢的析出行为和力学性能。结果表明,在800~1050℃随时效温度升高,由Cr_(2)N和σ组成的胞状相先增多后减少,900℃为鼻尖温度。固溶试样(1200℃-30 min)极限拉伸强度(UTS)、屈服强度(YS)和伸长率分别为958 MPa、517 MPa和77.4%。在900℃随时效时间延长,胞状相充分形核生长,促进晶间开裂,导致钢UTS和伸长率降低(时效120 min两者分别为797 MPa和13%),YS先降后升。时效5 min,晶界析出消耗Cr、Mo、N等强化元素,导致YS降至492 MPa。在30 min及更长时间时效后,胞状相增多、长大,析出强化作用增强,导致YS提高(时效120 min为535 MPa)。With the soaring prices of Ni and Mo,it is necessary to develop new high-performance and Ni-and Mosaving stainless steel.Based on the composition of the S32654,a new type of super austenitic stainless steel(SASS)with 24.5%Cr-17%Ni-5%Mn-6.3%Mo-0.7%N was prepared by pressure metallurgy and element synergistic control methods.The precipitation behavior and mechanical properties of the steel were studied.The results indicate that during isothermal aging at 800-1050℃,as the temperature increased,the cellar precipitates composed of Cr_(2)N andσphases first increased and then decreased,and 900℃was confirmed to be the precipitation nose temperature of the steel.The ultimate tensile strength(UTS),yield strength(YS)and elongation of solid solution sample(1200℃-30min)can reach 958 MPa,517 MPa and 77.4%.With the prolongation of aging time at 900℃,the cellular precipitates underwent nucleation and growth,which promoted intergranular cracking,resulting in a decrease in UTS and elongation(797MPa and 13%,respectively,after aging for 120min),and the yield strength(YS)first decreased and then increased.After 5min of aging,the formation of intergranular precipitates consumed solid solution strengthening elements such as Cr,Mo,and N,leading to the reduction of YS to 492MPa.After aging for 30min and longer,the number and size of cellular precipitates increased,leading to an increase in YS(535MPa,after aging for 120min).

关 键 词：超级奥氏体不锈钢 析出行为 力学性能 Σ相 Cr_(2)N析出相 

分 类 号：TG142.1[一般工业技术—材料科学与工程]