热处理方法对服役劣化转化炉管组织的影响  

Effect of Heat Treatment Method on Microstructure of Service Deterioration Conversion Furnace Tube

作　　者：李松林[1] 曹逻炜 韩志远[2] 程方杰 LI Songlin;CAO Luowei;HAN Zhiyuan;CHENG Fangjie(School of Materials Science and Engineering,Tianjin University,Tianjin 300350,China;China Special Equipment Inspection and Research Institute,Beijing 100029,China;Tianjin Key Laboratory of Advanced Joining Technology,Tianjin 300350,China)

机构地区：[1]天津大学材料科学与工程学院,天津300350 [2]中国特种设备检测研究院,北京100029 [3]天津市现代连接技术重点实验室,天津300350

出　　处：《热加工工艺》2021年第2期145-149,154,共6页Hot Working Technology

基　　金：国家重点研发计划项目(2017YFF0210401)。

摘　　要：采用在电炉中整体加热和TIG电弧表面加热两种方法,对服役7年左右的HP40Nb转化炉管材料进行了热处理试验,分析了采用两种热处理方法后转化炉管母材的显微组织、析出相形态及分布情况。结果表明:电炉整体热处理在980℃保温6 h后晶界碳化物内部发生部分溶解,网链状结构开始出现断裂;TIG电弧表面热处理后随着距离表面深度的增加微观组织差异明显,其中,细晶粒区深度最大可达2 mm,热影响区奥氏体晶内原析出物全部溶解,晶界析出物大量溶解呈网筛状。所提出的TIG电弧表面热处理技术可以用于旧转化炉管焊接修复中的坡口预处理。The heat treatment test of HP40 Nb conversion furnace tube material which had been in service for about 7 years was carried out by means of integral heating in electric furnace and TIG arc surface heating. The microstructure,morphology and distribution of precipitated phase in the base metal of converter tube after two heat treatment methods were analyzed. The results show that, the whole heat treatment of electric furnace is partially dissolved in the grain boundary carbide after heat treatment at 980 ℃ for 6 h. The net chain structure begins to crack. The microstructure of TIG arc surface is obviously different with the increase of surface depth after heat treatment, the maximum depth of fine grain zone can reach 2 mm, the original precipitates in austenite grains are all dissolved, and a large number of grain boundary precipitates dissolve in the shape of mesh. The TIG arc surface heat treatment technology proposed can be used to pretreat the groove in welding repair of old converter tube.

关 键 词：热处理 服役劣化 HP40Nb 微观组织 

分 类 号：TG156.99[金属学及工艺—热处理]