摘要
采用激光焊接方法对A286铁基高温合金薄板进行焊接,对焊接接头分别进行982℃固溶、982℃固溶+718℃时效热处理,研究了热处理对焊接接头显微组织和力学性能的影响。结果表明:未热处理时焊接接头焊缝组织主要由奥氏体、δ铁素体和γ’相组成;固溶处理后,接头焊缝中的δ铁素体含量增多,γ’相数量减少,接头强度、硬度与焊态相比变化不大,但断后伸长率由焊态的17.3%提升至22.7%;经固溶+时效处理后,接头焊缝组织中δ铁素体大部分转变为奥氏体,晶粒发生粗化,且析出大量弥散分布的γ’相,焊接接头的抗拉强度和屈服强度分别由固溶态的639,360MPa提升至1 019,662MPa,平均硬度达到了固溶态的200%,但断后伸长率降低至17.1%。
A laser welding method was used to conduct welding experiments on A286 iron-based superalloy thin plates and the welded joints were subjected to heat heatment with 982 ℃ solid solution,and 982 ℃ solid solution+718℃ aging.The influence of heat treatment on the microstructure and mechanical properties of welded joints was studied.The results show that the weld structure of the welded joint was mainly composed of austenite,δ ferrite and γ’ phases without heat heatment.After solid solution,the δ ferrite content in the joint weld increased,and the number of γ’ phases decreased;the strength and hardness of the joint changed little,compared with those at weld state,but the elongation after the fracture increased from 17.3% at the weld state to 22.7%.After solid solution+aging,most of the δ ferrite in the joint weld structure was converted to austenite,whose grains were coarsened;a large number of diffuse distribution γ’ phases were precipitated,and the tensile strength and yield strength of the welded joint increased from 639,360 MPa at solid solution state to 1 019,662 MPa;the average hardness reached 200% of solid solution state,but the elongation after the fracture was reduced to 17.1%.
作者
张兵宪
雷龙宇
杜明科
张云龙
张敏
ZHANG Bingxian;LEI Longyu;DU Mingke;ZHANG Yunlong;ZHANG Min(AVIC Xi'an Aircraft Industry Group Company LTD,Xi'an 710089,China;School of Materials Science and Engineering,Xi'an University of Technology,Xi'an 710048,China)
出处
《机械工程材料》
CAS
CSCD
北大核心
2022年第10期87-91,97,共6页
Materials For Mechanical Engineering
基金
国家自然科学基金资助项目(51974243)
中国博士后科学基金资助项目(2020M673449)
陕西省自然科学基础研究计划项目(2019JZ-31)
陕西省科技厅自然科学基础研究计划项目(2020JQ-637)
陕西省教育厅自然科学专项项目(19JK0590)。
关键词
激光焊接
热处理
微观组织
力学性能
铁基高温合金
laser welding
heat treatment
microstructure
mechanical property
iron-based superalloy