材料工程2025，Vol.53Issue(11)：80-89,10.DOI:10.11868/j.issn.1001-4381.2023.000169
NiCrMo合金焊接9Ni钢接头的焊缝组织与力学性能
Microstructure and mechanical properties of 9Ni steel joints welded by NiCrMo filler alloy
常子金 1齐彦昌 2马成勇 2从保强 3魏金山 2彭云2
作者信息
- 1. 钢铁研究总院有限公司 焊接研究所,北京 100081||北京航空航天大学 机械工程及自动化学院,北京 102206
- 2. 钢铁研究总院有限公司 焊接研究所,北京 100081
- 3. 北京航空航天大学 机械工程及自动化学院,北京 102206
- 折叠
摘要
Abstract
Welding of cryogenic 9Ni steel is performed using NiCrMo alloy systems with different Nb and C contents.The microstructure and mechanical properties of the welded joints are investigated,and the fracture toughness of the joints under ultra-cryogenic conditions is analyzed by crack tip opening displacement(CTOD)tests.The results show that the welded joint exhibits distinct zoning characteristics.The nickel-based weld metal primarily consists of an austenitic columnar crystal matrix and secondary phases.The secondary phases include fine nanoscale banded precipitates and Nb-rich solidification phases formed in the final stage of weld pool solidification.The precipitates are mainly composed of metal carbides(MC)and Laves phases.With the increase of Nb and C content,the number and average particle size of secondary phases in the nickel-based alloy increase,leading to an improved tensile strength of the joint,but reduced cryogenic impact toughness and fracture toughness.The load-notch opening displacement(F-V)curves show that the characteristic load Fm of the joint first increases and then decreases with the addition of Nb and C,while the corresponding characteristic plastic displacement value Vp decreases monotonically with the increase of secondary phases.The fracture surface of the CTOD specimens shows the same zoning characteristics.As the Nb and C content increases,the width of the stable crack propagation region on the fracture surface gradually decreases,indicating a deterioration in the fracture toughness of the weld.关键词
NiCrMo合金/9Ni钢焊接/Nb含量/微观组织/力学性能Key words
NiCrMo alloy/9Ni steel welding/Nb content/microstructure/mechanical property分类
矿业与冶金引用本文复制引用
常子金,齐彦昌,马成勇,从保强,魏金山,彭云..NiCrMo合金焊接9Ni钢接头的焊缝组织与力学性能[J].材料工程,2025,53(11):80-89,10.
