Joining of SiO2f/SiO2 composite to Nb using Ag-Cu-In-Ti brazing alloys

• 作者: Bo Chen Wen-Jiang Zou Wen-Wen Li Shi-Biao Wu Hua-Ping Xiong Xin Wu
• 来源期刊: 材料科学技术（英文版）
• 年，卷（期）: 2020,（15）
• 页码范围: 13-20
• 页数: 8页
• 语种: 英文

摘要

Three compositions of Ag-Cu-In-Ti system brazing alloys were designed for joining SiO2f/SiO2 ceramic composite to Nb metal.The wettability of the three alloys on the composite was studied with the ses-sile drop method.The results showed that after heating at 1073 K for 30 min,they exhibited contact angles of 74°,83° and 86°,respectively.The brazing alloys were fabricated into foils by rapid solidifi-cation technique.Among the three brazing filler alloys the joints brazed with AgCu-10In-5Ti at 1073 K for 10 min presented the maximum average shear strength of 30.9 MPa.During the brazing process the active element Ti diffused strongly from the filler alloy to the composite surface and a reaction layer with a thickness of 2-3 μm was formed.Sound metallurgical bonding was also achieved at the Nb side.The interface structure of the joint brazed with the AgCu-10In-5Ti alloy can be described as the follow-ing sequence:SiO2f/SiO2 →SiO2+Cu3Ti3O→SiO2+TiO+Ti5Si4→Ag(s,s)+(Cu-Ti)-→Nb.However,for the filler alloy with 4.0 wt％ Ti content the joint strength was only 15.8 MPa.