合金元素对正火+回火3.5Ni钢组织与性能的影响  

Effect of Alloying Elements on Microstructures and Properties of 3.5Ni Steel by Normalizing and Tempering

作　　者：朱莹光 徐海健 张宏亮 杜林 侯家平 严平沅 ZHU Yingguang;XU Haijian;ZHANG Hongliang;DU Lin;HOU Jiaping;YAN Pingyuan(State Key Laboratory of Metal Material for Marine Equipment and Application,Anshan114009,Liaoning,China;Ansteel Iron&Steel Research Institutes,Anshan 114009,Liaoning,China;Angang Steel Co.,Ltd.,Anshan 114021,Liaoning,China)

机构地区：[1]海洋装备用金属材料及其应用国家重点实验室,辽宁鞍山114009 [2]鞍钢集团钢铁研究院,辽宁鞍山114009 [3]鞍钢股份有限公司,辽宁鞍山114021

出　　处：《鞍钢技术》2025年第1期29-32,46,共5页Angang Technology

摘　　要：在3.5Ni钢中分别添加Mo、Nb、Ti和Mo、V合金元素,采用直接轧制和控制轧制两种轧制方式,探究合金元素和轧制方式对正火+回火处理后组织和性能的影响。结果表明,合金元素的添加使得热轧态组织中出现了贝氏体,大幅度提高了热轧态钢板的强度,为后续采用正火+回火处理提供了保障。采用直接轧制方式,热轧后晶粒长得很大,正火+回火处理很难消除原始粗化组织对性能的影响,导致钢板低温冲击韧性非常低。控制轧制后晶粒显著细化,并促进了贝氏体的形成,提高了钢的强度和低温韧性。Nb、Ti对贝氏体的形成以及组织的细化作用强于V,因此,含Mo、Nb、Ti合金的3.5Ni钢的综合力学性能更好。By separately adding Mo+Nb+Ti and Mo+V alloy elements into the 3.5Ni steel and using two kinds of rolling methods consisting of direct rolling and controlled rolling,the effects of alloy elements and these two rolling methods on its microstructures and properties after treatment by normalizing and tempering(NT)were investigated.The study results showed that the addition of these alloying elements resulted in the appearance of bainite in the steel's hot-rolled microstructures,which greatly improved the strength of a hot-rolled steel sheet and also provided the guarantee for subsequent normalization and tempering treatment.If the direct rolling method was used,the grains in the steel grew so large after hot rolling that it was difficult to eliminate the effect of the original coarsened microstructures on the properties by NT treatment,resulting in very low impact toughness of the steel sheet at low temperature.However,after the controlled rolling method was used,the grains were obviously refined and the formation of bainite was promoted,and therefore the strength and low temperature toughness of the steel were improved.And what's more,the elements of Nb and Ti had stronger effect on the formation of bainite and refinement of microstructures than the element of V,and so the comprehensive mechanical properties of the 3.5Ni steel containing Mo,Nb and Ti alloy elements were much better.

关 键 词：3.5NI钢 合金元素 控制轧制 正火+回火 贝氏体 

分 类 号：TG142[一般工业技术—材料科学与工程]