摘要
通过力学性能试验、光学金相显微镜、扫描电子显微镜、透射电子显微镜研究了S31042钢使用82型焊材焊接接头高温时效后的显微组织和力学性能.结果表明,650℃时效3 000 h后,接头的室温抗拉强度和硬度略有升高,但上升幅度低于同材质焊材接头;82型焊材焊接接头的高温持久强度低于同材质焊材接头,只能达到同材质焊接接头的88%.高温时效会使82型焊材焊缝的缺口冲击吸收功下降,但始终保持在70 J以上;82型焊材焊缝强度不足是导致该接头室温强度、持久强度低于同材质焊材焊接接头的主要原因;82型焊材焊缝强度主要源于合金元素的固溶强化,晶界处球状M23C6相的连续网状及亚晶界处针状δ相的簇状分布,对强度提高作用较小,但会降低焊缝的冲击韧性.
Microstructure and mechanical properties of S31042 steel welded joints with 82 alloy filler metal were investigated by mechanical properties test(MT),optical microscope(OM),scanning electron microscope(SEM) and transmission electron microscope(TEM). The results showed that the tensile strength and hardness of S31042 welded joints increased slightly when the aging time was longer than 3 000 h,but the strength and hardness growth was lower than that with similar filler metal.The creep rupture strength of welded joints with 82 alloy filler metal can only reach about 88% of that with similar filler metal.The Charpy impact toughness can be obtained above 70 J,though it decreased after long term thermal exposure. The strength insufficiency of 82 alloy weld metal should be the main reason for lower tensile strength and creep rupture strength of welded joint.The 82 alloy weld metal was strengthened by solid solution. The clustered distribution of net-like δ phase and existence of spherical M23 C6 phase along grain boundary reduced the impact toughness and had little strengthening effect on the weld metal.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2017年第12期119-124,共6页
Transactions of The China Welding Institution
作者简介
刘福广,男,1981年出生,硕士,高级工程师.主要从事电站重要承压部件的焊接、热处理技术及其高温运行过程中的组织性能研究.发表学术论文10余篇.Email:liufuguang@tpri.com.cn
