钛及钛合金电弧钎焊及接头强度

Interface Behavior and Joint Strength by TIG Arc Brazing for Titanium and Titanium Alloy

用Ti-Cu-Ni,Ti-Cr-Zr钎料在TIG电弧加热条件对TA2和Ti-6Al-4V钛合金进行钎焊。结果表明:用Ti-Cu-Ni钎料钎焊TA2和Ti-6Al-4V钛合金的搭接接头强度分别是418.3MPa和439.6MPa;用Ti-Cr-Zr钎料钎焊TA2和Ti-6Al-4V钛合金的搭接接头强度分别是575.2MPa和656.1MPa。对Ti-Cu-Ni钎料/母材界面分析认为固液异分化合物η相((Cu,Ni)Ti2)生成时呈笋状生长,嵌入钎缝对钎缝的强度提高有利。对Ti-Cr-Zr钎料/母材界面分析,认为主要是固溶体β-Ti(Cr)存在提高了钎缝强度。

Industrial pureity Ti and Ti-6Al-4V alloy were TIG-arc brazed using Ti-Cu-Ni and Ti-Cr-Zr as brazing filler metals. The experimental results show that for industrial purity Ti and Ti-6Al-4V, respectively, the overlap brazing joint strength are 418.3 MPa and 439.6 MPa by using Ti-Cu-Ni as the brazing filler metal, and 575.2 MPa and 656.1 MPa by using Ti-Cr-Zr as the brazing filler metal. Analyzsis of the interface between the Ti-Cu-Ni brazing filler metal and the base metal, it is found that an incongruent compound eta phase (Cu, Ni)Ti-2 grows in the shape of a bamboo shoot embedded in the brazing seam during arc brazing, increasing the brazing joint strength for the interface between the Ti-Cr-Zr brazing filler metal and the metal, there exists a solid solution beta Ti(Cr) as the major phase, which also increases the brazing joint strength.