中国电力 ›› 2016, Vol. 49 ›› Issue (2): 1-5.DOI: 10.11930/j.issn.1004-9649.2016.02.001.05

• 发电 • 上一篇    下一篇

预热和焊后热处理对T23钢接头力学性能的影响

李夕强1,王学2,杨超1,葛兆祥1,杨贤彪1,任遥遥2   

  1. 1.江苏方天电力技术有限公司,江苏 南京 211102;
    2.武汉大学 动力与机械学院,湖北 武汉 430072
  • 收稿日期:2015-10-08 出版日期:2016-02-18 发布日期:2016-03-21
  • 作者简介:李夕强(1973-),男,江苏南京人,高级工程师,从事电站金属监督、理化分析及无损评估方面的研究。E-mail: lee0178@sina.com
  • 基金资助:
    国家自然科学基金资助项目(51574181);先进焊接与连接国家重点实验室开放课题重点资助项目(AWJ-Z15-02)

Effects of Preheating and Post-Weld Heat Treatment on the Mechanical Properties of T23 Steel Weldment

LI Xiqiang1, WANG Xue2, YANG Chao1, GE Zhaoxiang1, YANG Xianbiao1, REN Yaoyao2   

  1. 1. Jiangsu Frontier Electric Technology Co. Ltd., Nanjing 211102, China;
    2. School of Power and Mechanics, Wuhan University, Wuhan 430072, China
  • Received:2015-10-08 Online:2016-02-18 Published:2016-03-21
  • Supported by:
    This work is supported by the National Natural Science Foundation of China(No. 51574181) and State Key Lab of Advanced Welding and Joining, Harbin Institute of Technology (No. AWJ-Z15-02).

摘要: 为优化焊接工艺,解决水冷壁T23接头焊缝在运行中容易出现裂纹的问题,测试了T23接头在4种不同工艺(不预热、焊后不热处理,不预热、焊后热处理,预热、焊后不热处理,预热、焊后热处理;预热温度为150 ℃,焊后热处理工艺为740 ℃、0.5 h)下的硬度和冲击韧性,并观察了显微组织的变化。研究结果表明,预热对T23接头硬度的影响不大,但增大晶粒尺寸和过热区的宽度,对焊缝和热影响区(HAZ)的韧性均有不利影响;焊后热处理明显降低焊缝和HAZ的硬度,虽然对HAZ韧性影响很小,但可改善焊缝的韧性。建议预热温度不超过150 ℃或取消预热,进行焊后热处理以保证接头的长期服役性能。

关键词: T23钢, 焊接接头, 预热, 焊后热处理, 力学性能

Abstract: In order to optimize the welding techniques of T23 steel and avoid the cracking in its welded joints in the water-wall of ultra supercritical(USC) boilers, the hardness and toughness are tested for the joints welded with four different welding techniques, which are the ones of without preheating and post-weld heat treatment(PWHT), PWHT without preheating, preheating without PWHT, preheating and PWHT. The preheating is set at 150 ℃ and PWHT being at 740 ℃ for 0.5 h. The changes of their microstructures are also observed. The results show that preheating has little effect on the hardness of the weldments, but it makes the grain size and width of the over-heated zone enlarge, which lowers the toughness of the weld metal and the heat-affected zone (HAZ). PWHT significantly reduces the hardness of the weld metal and HAZ, and improves the toughness of the weld metal even though it has little effect on that of HAZ. In order to avoid the occuring of cold cracking, preheating with the temperatures below 150 ℃ or no prheating is recommended for the welding of T23 steel. For the sake of long-term operating properities of the T23 steel joints, PWHT is still necessary for the improvement.

Key words: T23 steel, welded joint, preheating, post-weld heat treatment, mechanical properties

中图分类号: