T23钢斜Y试样的时效再热开裂  

Aging Cracking Study on Y-groove Sample of T23 Steel

作　　者：张波[1] 李强[1] 亓安芳[1] 金用强[1] 

机构地区：[1]上海锅炉厂有限公司,上海200245

出　　处：《锅炉技术》2013年第1期48-52,共5页Boiler Technology

基　　金：上海市科学技术委员会科研资助项目(10dz1201201)

摘　　要：研究了超(超)临界锅炉水冷壁用T23钢在工作温度下的再热开裂行为。在箱式电阻炉中对成分改良前后的T23钢斜Y型拘束试样于500℃进行时效试验;用X-Ray探伤仪定期对时效斜Y试样的试验焊道进行无损检测;用光学和电子显微镜对已经开裂的试样进行裂纹形态和组织分析;用维氏硬度计测试开裂试样的焊缝、热影响区和母材的硬度。结果表明:预先施加应力的试验焊道,在500℃的时效温度下,于2 000h以后,在HAZ的过热区先后发生开裂。说明未经焊后热处理的T23接头在工作温度较低的工况下仍然存在再热开裂倾向,且表现出明显的滞后开裂特征。Reheat cracking behavior of T23 steel at operating temperature,which is used as water wall in ultra-supercritical boiler,has been studied.Long aging test of y-groove restraint weld sample of T23 steel with pre and post modified composition is done in box resistorstove at 500℃.Experimental welding bead of aged y-groove weld sample is detected by NDT with X-ray flaw detector.Crack morphology of cracked sample is analyzed with optical and electron microscopy.The weld,HAZ and base metal hardness of cracked sample is tested with Vickers hardness tester.After aging for 2000 hours at 500℃,prestressed experimental welding bead has successively been cracked at overheated zone,which shows that T23 weld joint without PWHT has reheat cracking trend and obvious delayed cracking characteristics at low working temperature.

关 键 词：斜Y试样 低温时效 滞后开裂 再热裂纹 

分 类 号：TG441.1[金属学及工艺—焊接]