Al <sub> 2 </ Sub> The O <sub> 3 </ Sub> Diffusion Of Copper / The T2 Copper Vacuum Diffusion Welding Research

Softening temperature of Al₂O₃ dispersion-strengthen copper is up to 930℃, it's tensile strength is up to 600MPa and good conductivity of 86.49%IACS. The lifetime of Al₂O₃ dispersion-strengthen copper is 4 to 10 times more than CuCrZr alloy electrode. Using Al₂O₃ dispersion-strengthened copper alloy to replace the CrZrCu alloy electrode to make composite components with T2 copper, through diffusion welding process, can improve working efficiency and save alot of energy.In this paper, Al₂O₃ dispersion-strengthen copper/T2 copper was bonded together by vacuum diffusion bonding technology. The microstructure feature of the joint interface was investigated by optical microscope and scanning electron microscope. The influence of diffusion bonding parameters on interface combining state and microstructure of Al₂O₃ dispersion-strengthen copper/T2 copper interface was studied. The jiont consists of three parts: I area is near T2 copper; II area is in the seam center; III area is near Al₂O₃ dispersion-strengthen copper. With the increase of heating temperatuer the transition zone width of the Al₂O₃ dispersion-strengthen copper/T2 copper interface broadened and the The Grain Growth in transition zone. Ti aggregated at the edge of Al₂O₃ dispersion-strengthen copper and T2 copper in the brazing process, and it's much more obvious at the Al₂O₃ dispersion-strengthen copper side.The most influential factor on the adhensive strength of the joint was difussion temparature,followed by pressure and holding time, analysised by orthorhombic-experiment method.and the means of orthogonal result show that the optimized paramenters for the joint were gained as fellows: diffusion temperature was 550℃, holding time was 3 h, pulse pressure was25MPa. The jointstrength under the optimum condition was 166.9MPa. The microstructure feature of the Al₂O₃ dispersion-strengthen copper/T2 copper joint interface was investigated by optical microscope and scanning electron microscope in the optimized paramenters and the joint interface bounding well.There is no Confucianism and crack.Compositions in I district of the joint interface were the Cu(Ti)solid solution and a small amount of Cu-Ti compounds, Cu-Ti compounds in II district mainly, Cu(Ti)solid solution, Cu-Ti compounds and a very small amount of Ti-O compounds in III district The microstructuer, interface formation mechanism and interface fracture of Al₂O₃ dispersion-strengthen copper/T2 copper diffusion bonding joint were sdudied in the paper. The studies can provide experiental basis and theoryfoundation for the wide application of Al₂O₃ dispersion-strengthen copper/T2 copper.