摘要
针对SiO_(2f)/SiO_(2)复合材料与蓝宝石活性钎焊接头界面脆性化合物多,接头残余应力大易开裂的问题,设计并制备了CNT-AgCuTi复合中间层辅助钎焊.结果表明,钎焊过程中CNT与Ti元素发生原位反应,有效抑制了团聚的TiCu脆性相生成,在钎缝中形成大面积的Ag(s, s)+TiC组织以及少量的TiCu_(4)相,SiO_(2f)/SiO_(2)复合材料与蓝宝石界面形成连续致密的反应层,并且在两种母材界面附近形成塑韧性较好的Ag-Cu共晶组织,有利于缓解接头残余应力.在880℃/10 min的工艺参数下,采用质量比为10∶4的CNT-AgCuTi复合中间层辅助钎焊SiO_(2f)/SiO_(2)复合材料与蓝宝石,接头抗剪强度从3 MPa提升至26 MPa.该方法可为其它活性钎焊体系调控界面组织及改善接头性能提供试验依据和理论基础.
To solve the problems of excessive brittle compounds at the interface and high residual stress which easily leads to cracking in the active brazed joint between SiO_(2f)/SiO_(2) composite and sapphire,a CNT-AgCuTi composite interlayer was designed and prepared for auxiliary brazing.The results show that the in-situ reaction between CNT and Ti element during brazing effectively inhibits the formation of agglomerated TiCu brittle phase,and a large area of Ag(s,s)+TiC structure,as well as a small amount of TiCu_(4) phase is formed in the brazing seam.Continuous and dense reaction layers are formed at the interfaces between the SiO_(2f)/SiO_(2) composite and sapphire,and an Ag-Cu eutectic structure with excellent plasticity and toughness is formed near the interfaces of the two base materials,which is conducive to relieving the residual stress of the brazed joint.Under the brazing parameters of 880℃/10 min,by using the CNT-AgCuTi composite interlayer with a mass ratio of 10∶4 for auxiliary brazing of SiO_(2f)/SiO_(2) composite and sapphire,the shear strength of the brazed joint is increased from 3 MPa to 26 MPa.This method can provide experimental and theoretical bases for regulating the interfacial microstructure and improving the joint performance in other active brazing systems.
作者
常青
丁畅
孙湛
张博
阿合那尔·对山
张丽霞
CHANG Qing;DING Chang;SUN Zhan;ZHANG Bo;AHENAER·Duishan;ZHANG Lixia(State Key Laboratory of Precision Welding&Joining of Materials and Structures,Harbin Institute of Technology,Harbin,150001,China)
出处
《焊接学报》
北大核心
2025年第11期20-27,共8页
Transactions of The China Welding Institution
基金
国家自然科学基金资助项目(U2167216,52475335)
国家重点研发计划项目(2021YFB3401102)。
