摘要
为了缓解C/C复合材料与TC_(4)合金钎焊接头的残余应力,采用AgCuTi+0.3%C_(f)钎料实现了二者的连接。使用扫描电子显微镜、透射电子显微镜确定了界面微观组织结构,利用万能试验机表征接头的力学性能,对不同钎焊温度下的接头界面组织及力学性能进行了分析,并归纳了钎焊接头形成过程,阐明了碳纤维在接头形成过程中的作用机理。结果表明:随着钎焊温度的升高,由于Ti活度以及元素扩散速率的增加,接头两侧的反应层厚度增加,钎缝中心的Ti-Cu化合物增加,相应的钎焊接头抗剪强度先增加后减小,在钎焊温度900℃,钎焊时间10min时获得最大接头强度28.5MPa。C/C/AgCuTi+C_(f)/TC_(4)接头形成可以分为钎料熔化,TC_(4)开始溶解;元素富集,反应层形成;等温析出,液相推移;接头形成4个阶段。碳纤维在接头形成中起到组织调控与应力调控作用,这使钎焊接头质量得到提升。
C/C composite and TC_(4) alloy were brazed successfully by using AgCuTi+0.3%C_(f) filler.The interfacial microstructure was investigated by the SEM,EDS and TEM.The mechanical property of the joints was characterized by the universal testing machine.The microstructure and mechanical property of the joints brazed at different temperatures were analyzed.The process of joint formation was analyzed,and the role of carbon fiber in each stage of joint formation was revealed.Results show that with the increase of the brazing temperature,Ti activity and element diffusion rate increased,so that the thickness of reaction layers on both sides of joints and Ti-Cu compounds in the center of brazing seam increased.The shear strength of joints first increased and then decreased with the increase of brazing temperature,and the maximum strength of 28.5 MPa was obtained when the brazing temperature was 900℃and the holding time was 10 min.The formation process of C/C/AgCuTi+C_(f)/TC_(4) joints could be divided into four stages:melting of filler,and dissolving of TC_(4)alloy;element enrichment,and formation of reaction layer;isothermal precipitation,and movement of liquid phase;joint formation.Carbon fiber played an important role in the formation of the joint,which regulated the microstructure and residual stress of the brazed joint and improved the mechanical property of brazed joint.
作者
赵可汗
刘多
朱海涛
陈斌
胡胜鹏
宋晓国
ZHAO Kehan;LIU Duo;ZHU Haitao;CHEN Bin;HU Shengpeng;SONG Xiaoguo(State Key Laboratory of Advanced Welding and Joining,Harbin Institute of Technology,Harbin 150001,China;Shandong Provincial Key Lab of Special Welding Technology,Harbin Institute of Technology at Weihai,Weihai 264200,China)
出处
《航空学报》
EI
CAS
CSCD
北大核心
2022年第4期464-474,共11页
Acta Aeronautica et Astronautica Sinica
基金
国家自然科学基金(51875130,51775138)
山东省自然科学基金(ZR2019MEE091)。
