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Ti 2 AlNb alloy has a high melting point, low density, elastic modulus, high temperature oxidation resistance, has been more widely used in the field of aerospace, as an important structural materials how to solve welding problems have important practical significance. In this paper, the application needs of the aerospace industry, the Ti connection 2 AlNb alloy radiant heating vacuum brazing and transient liquid phase diffusion study, analysis of the different connection methods, under the conditions of different solder connection parameters connector interface structure characteristics and shear strength of the law, to determine the best connection specification parameters under different connection process. TiZrNiCu brazing material uses the radiation heating the vacuum brazing Ti 2 AlNb alloy at the interface of Ti 2 Ni, Ti (Cu, Al) 2 intermetallic compound and Ti -Zr-based solid solution generated. With the increase in the bonding temperature and holding time, Ti, Al, Ni, Cu element diffusion reaction more fully, Ti 2 Ni and Ti (Cu, Al) 2 increased Ti-Zr-based solid solution of the reduction; lot of TI 2 the formation of the Ni and Ti (Cu, Al) 2 reduces the shear strength of the joint; when connecting a temperature of 940 ° C, the connection time of 10min, the maximum shear strength of the joint is 225MPa. The solder to TiNiNb using radiant heat the vacuum brazing Ti 2 AlNb alloy at the interface of Ti 2 AlNb, of Ti3Al, TiNi, Ti 2 2 Ni, Ti-based solid solution dispersed in TiNi play an enhanced role of the connector. With the increase in the bonding temperature and time, Ti 2 Ni of Ti3Al and TiNi compounds increase, decrease in Ti-based solid solution, intermetallic compounds fused joints, so the joints brittle fracture characteristics, the interface at the cracks, reducing the strength of the joint, the strength of the joint to render the law first and then decreased with the brazing temperature and time. Bonding temperature T = 1160 ℃, when connection time 20min, the shear strength of the joints to 308MPa. Ni / Ti / Ni laminated TLP welding Ti 2 AlNb alloy at the interface of Ti 2 AlNb, AlNb 2 , TiNi, Ti < sub> 2 Ni compounds generated, connect the interface between lot of Ti 2 Ni and a small amount of TiNi brittle phase. Holding time distribution in the form of the brittle phase, always presents the distribution of patchy connection at the interface. However the connection temperature TI 2 Ni brittle phase morphology distribution have a greater impact in the appropriate connection temperature Ti 2 Ni in the connecting region obvious dispersed state , serving to strengthen joints role, when the welding time was 120min, the temperature of 1000 ° C to obtain joint maximum shear strength of 323MPa. The further increase welding temperature, diffusion reaction layer thickness increases, dissolved base metal increases in isothermal solidification process relatively prolonged the Ti 2 Ni presented at the joint the strip distribution state, the declining strength of the joint state.
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