摘要
奥氏体304LN不锈钢广泛应用于核工业中。利用TIG焊接来焊接不锈钢板,在304LN焊接接头处取样,分别以2 K/min和5 K/min速率及液氮浸泡的方式进行深冷处理,利用THVS-1MDX-AXY半自动显微维氏硬度计检测深冷前后304LN焊接接头的焊缝、母材、熔合区及热影响区的显微硬度分布及变化特征。研究表明:深冷处理并不会大幅度地改变焊缝组织结构,且随着碳氮化物的析出,组织逐渐趋于稳定,所以深冷处理对焊缝硬度的影响是有限的,但是对304LN焊接件以2 K/min降温速率进行深冷处理可以在最大程度上提高焊接接头的硬度值。
Austenitic 304 LN stainless steel is widely used in nuclear industry. TIG welding was used to weld stainless steel sheets. The 304 LN welded joints were sampled, and the cryogenic treatment of the sample was carried out at 2 K/min and 5 K/min rates or by immersing in liquid nitrogen. The microhardness distribution and variation characteristics of weld seam, base metal, fusion zone and heat affected zone of 304 LN welded joints before and after cryogenic treatment were measured by THVS-1 MDX-AXY semi-automatic microhardness tester. The results show that cryogenic treatment does not change the microstructure of weld seam greatly, and as the carbonitride precipitates, the microstructure tends to be stable,so the effect of cryogenic treatment on the hardness of weld is limited, but the hardness of 304 LN welding part can be improved to the greatest extent by cryogenic treatment at a cooling rate of 2 K/min.
作者
李扬
游凡
沈子豪
LI Yang;YOU Fan;SHEN Zihao(School of Civil Architecture and Environment,Hubei University of Technology,Wuhan 43006&China;Department of Civil Engineering,Shanghai University,Shanghai 200444,China)
出处
《热加工工艺》
北大核心
2021年第5期31-34,共4页
Hot Working Technology
基金
国家自然科学基金资助项目(51508171)。
