摘要
304LN不锈钢板焊接件在焊接接头处取样分别以2℃/min和5℃/min速率进行深冷处理,对其深冷前后显微组织和力学性能变化进行分析。试验结果表明:深冷处理使得材料内部奥氏体向马氏体转化,并伴有碳化物和氮化物的析出。以5℃/min速率进行深冷处理,相较于2℃/min深冷速率析出物数量更多且分布更加均匀;深冷处理使得304LN不锈钢板焊接接头抗拉强度和冲击韧性得到提高。与未处理试样相比,经历3次2℃/min深冷处理试样抗拉强度和冲击韧性分别提高了1. 24%和16%,经历3次5℃/min深冷处理试样抗拉强度和冲击韧性分别提高了4. 77%和23%。综合考虑两种深冷工艺,以5℃/min深冷处理能获得最佳的力学性能,该工艺可作为304LN不锈钢板焊接接头增强增韧处理方法。
Sampling at the welded joints of 304 LN stainless steel plate weldments,and the samples were cryogenic treated at a rate of2℃/min and 5℃/min,respectively.The microstructure and mechanical properties of the 304 LN stainless steel plate welded joints were analyzed before and after cryogenic treatment.The experimental results show that deep cryogenic treatment promotes martensite transformation from austenite,and accompanied by precipitation of carbides and nitrides.When cryogenic treated at a rate of 5℃/min,there are more carbides and nitrides precipitated and evenly distributed compare with that treated at 2℃/min.The deep cryogenic treatment can improve the tensile strength and impact toughness of the 304 LN stainless steel plate welded joint with respect to untreated samples.The tensile strength and impact toughness of the samples subjected to cryogenic treatment at rate of 2℃/min for 3 times are increased by 1.24%and16%,respectively.After cryogenic treatment at rate of 5℃/min for 3 times,the tensile strength and impact toughness of the samples are increased by 4.77%and 23%,respectively.Hence,it is better to apply the cryogenic treatment at rate of 5℃/min for the 304 LN stainless steel plate weldments.This process can be used as a strengthening and toughening method for the 304 LN stainless steel plate welded joints.
作者
沈子豪
李扬
刘奎周
Shen Zihao;Li Yang;Liu Kuizhou(School of Civil Architecture and Environment,Hubei University of Technology,Wuhan Hubei 430068,China)
出处
《金属热处理》
CAS
CSCD
北大核心
2019年第8期181-184,共4页
Heat Treatment of Metals
基金
湖北工业大学科研启动基金(BSQD14044)
关键词
304LN不锈钢板焊接件
深冷处理
显微组织
力学性能
304LN stainless steel plate weldment
deep cryogenic treatment
microstructure
mechanical properties
