超(超)临界锅炉管用材料的缺陷和失效分析  

ANALYSIS OF DEFECTS AND FAILURE FOR TUBE MATERIALS USED ON BOILERS OF ULTRA-SUPERCRITICAL UNITS

作　　者：赵永宁[1] 刘爽[1] 魏玉忠 

机构地区：[1]山东电力研究院,山东济南250002 [2]华电邹县发电厂,山东邹县273522

出　　处：《热力发电》2010年第4期36-41,共6页Thermal Power Generation

摘　　要：铁素体耐热钢和奥氏体不锈耐热钢制超（超）临界锅炉管在投入运行后，容易出现焊接接头裂纹、内壁氧化皮脱落等问题。对T91、T92钢管在运行中发生的过热爆管进行了组织性能分析，表明胀粗部位金相组织为细碎的白亮铁素体、碳化物和灰色岛状组织；爆管的拉伸强度Rp0．2和硬度值与吹损管相比均显著下降，爆口尖端的维氏硬度最低值下降到162，而相邻胀粗未爆管的维氏硬度值为175～187。The problems easily occurred on ferritic heat- resisting steel and austenitic stainless heat- resisting steel tubes used on boilers of ultra- supercritical units after putting them into operation, such as cracking on the weld joints,dropping of oxide skin from inner wall,etc. ,as well as over- temperature tube- burst occurred in operation of T91 and T92 steel tubes,have been analysed from aspects of microstructure and performance. It shows that the metallographic structure at thick - expanding location is white and bright fine ferritic carbide and grey island structure;the tensile strength Rpo. 2,RM, and hardness of bursted tube all have been considerably deacreased as compared with the blow- demaged tubes,the lowest value of diamond penetrator hardness at sharpened end of the burst hole has decreased to 162,while the said hardness value of the neighboaring thick- expanding tubes without burst is 175-187.

关 键 词：超(超)临界 锅炉管 铁素体耐热钢 奥氏体不锈耐热钢 焊接 裂纹 氧化皮 爆管 

分 类 号：TG142.23[一般工业技术—材料科学与工程] TG142.25[金属学及工艺—金属材料]