LIQUID PHASE DIFFUSION JOINING METHOD OF HEAT RESISTANT SUPERALLOY

PURPOSE:To improve joint strength by forming an extremely thin layer of an Al alloy contg. >=1 kinds selected from the group consisting of Si, Ge, Pd, etc. deposited by evaporation on at least one of joining materials then melting the layer deposited by evaporation thereby executing liquid phase diffusion joining. CONSTITUTION:An Al alloy plate 3 is formed of an Al alloy contg. at least >=1 kinds selected from the group consisting of Si, Ge, Pd, In, La, Ce, Te and Cu. A high voltage is impressed to the plate 3 as cathode and a joining material 1 consisting of a heat resistant superalloy as anode to form an extremely thin layer 2 deposited by evaporation on the joint surface. The material 1 formed with the layer 2 is moved into a joining chamber B and another superalloy joining material 5 is brought into contact therewith and both materials are pressed by a jig 6. The materials are then subjected to a liquid phase diffusion treatment in an electric furnace in which a protective atmosphere of gaseous Ar or the like is maintained. The structure of the joint part having the good distribution condition of a gamma phase is obtd. and the joint strength is improved by the above-mentioned method.