Study on microstructure of dissimilar welded joint of candidate alloys for 700 ℃ ultra supercritical unit boiler in service

ZHANG Jie; YIN Hongfei; LYU Haitao; SHI Weidong; GUO Tong; WEN Zuowei

doi:10.19666/j.rlfd.202201018

English

您当前的位置：

首页 >

文章列表页 >

Study on microstructure of dissimilar welded joint of candidate alloys for 700 ℃ ultra supercritical unit boiler in service

Thermal Power Generation Vol. 51, Issue 8, Pages: 180-186(2022)

更新时间：2025-09-28

- Study on microstructure of dissimilar welded joint of candidate alloys for 700 ℃ ultra supercritical unit boiler in service
- 作者机构：
  
  1. 华能秦煤瑞金发电有限责任公司
  2. 西安热工研究院有限公司
- 作者简介：
- 基金信息：
- DOI：10.19666/j.rlfd.202201018
  CLC： TG407;TM621.2
- Published：2022
- 稿件说明：
移动端阅览
ZHANG Jie, YIN Hongfei, LYU Haitao, et al. Study on microstructure of dissimilar welded joint of candidate alloys for 700 ℃ ultra supercritical unit boiler in service[J]. Thermal Power Generation, 2022, 51(8): 180-186.
DOI：

ZHANG Jie, YIN Hongfei, LYU Haitao, et al. Study on microstructure of dissimilar welded joint of candidate alloys for 700 ℃ ultra supercritical unit boiler in service[J]. Thermal Power Generation, 2022, 51(8): 180-186. DOI： 10.19666/j.rlfd.202201018.

摘要

对700℃超超临界燃煤发电机组关键部件验证试验平台运行1万h的TG700A和HT700T的锅炉合金管异种焊接头进行取样品分析，研究了服役态焊接接头微观组织和硬度的演化。结果表明：服役后，焊缝中富Mo、Ti元素的一次碳化物稳定存在于枝晶间，熔合线两侧合金元素未发生明显的互扩散；焊接热影响区晶界碳化物发生轻微粗化，且硬度与母材相当；内壁蒸汽氧化层以氧化铬为主，热影响区与母材氧化层形貌均无差别，平均厚度约为7μm，在服役工况下属于完全抗氧化级；经过1万h服役后焊接接头的组织稳定性良好。

Abstract

The weld joint of TG700A and HT700T which is used in superheater of ultra supercritical power plant boiler was studied after 10 000 h service on 700 ℃ ultra supercritical coal-fired power unit key component verification test platform. The evolution of microstructure and microhardness of the in-service weld joint was investigated. The results show that

after being put into service

the Mo/Ti-rich primary carbides distributed in interdendrite

and there was no obvious inter diffusion on both sides of the fusion line. Coarsening of grain boundary carbides occurred in the heat affected zone(HAZ)

and microhardness of the HAZ was consistent with the base metal. The steam oxide layer on inner wall was mainly chromium oxide

and the morphology of the HAZ was the same as that of the oxide layer of the base material. The average thickness of the oxide layer was about 7 μm

which was excellent oxidation resistance under the service conditions. The microstructure stability of the welded joint was good after 10 000 h service.

关键词

Keywords

references

Views

下载量

CSCD

Alert me when the article has been cited

提交

Publicity Resources

STUDY ON SERVICING BEHAVIOR OF BOILER TUBES MADE FROM 18-8 TYPE AUSTENITIC STAINLESS STEEL(6)

FEATURES OF WELDING TECHNOLOGY CONCERNING TITANIUM-STEEL COMPOSITE PLATE OF INTERNAL STEEL BARREL SHELL IN 201 m CHIMNEY

CAUSE ANALYSIS OF DESUPERHEATER FRACTURE FOR BOILER OF 600 MW UNIT

WELDING OF DISSIMILAR STEELS IN MANUFACTURING LOW β VALUE FEED-WATER FLOW NOZZLES

CAUSE ANALYSIS OF CONTINUOUS TUBE BURST ON HOLDING PIPES OF THE SCREEN-TYPE REHEATER FOR BOILER NO1 IN ONE POWER PLANT

Related Author

WANG Hongzhe Xi'an Thermal Power Research Institute Co Ltd

SHI Zhigang

HE Xipeng

ZHENG Fangping

ZHANG Lei

MA Hong

HUANG Hui-xian

ZHUANG Hai-qing

Related Institution

Jiangsu Electric Power Construction Third Company

Datang Panshan Power Generation Co., Ltd

Dalian Jinggong Automatic Control Instrument Complete Technology Development Company

Gansu Electric Power Research Institute

Hebei Electric Power Research Institute

AI问答

⁰