| 摘要 |
PURPOSE:To form joined parts of outstanding high-temp. corrosion resistance and high-temp. strength in the stage of welding Ni-based heat resistant alloy products of intricate shapes such as high-temp. gas turbines by forming an Al layer as a filler metal then subjecting the products to liquid phase diffusion bonding. CONSTITUTION:Structural members 1, 1' of high-temp. gas turbine blades consisting of Ni-based heat resistant alloys are precison-cast tne after the fayed surfaces are subjected to size matching, polishing, degreasing a cleaning, these are put in the 1st vacuum vessel 3, where an Al vapor deposition layer as a filler metal is formed by the Al vapor from an Al vapor source 6. These are transferred into the 2nd vacuum vessel 4, where the members are hot-pressed under vacuum with dies 10, 10' while heating with high frequency heating coil 8, and are joined via the Al vapor deposition layer. Further, these are heated to temps. higher than 660 deg.C which is a melting temp. for Al to allow the Al to diffuse into the Ni-based heat resistant alloy and to convert the joined parts to the structures of NiAl-beta phase Ni3Al-gamma' phase Ni3Al-gamma'+gamma phase, whereby the joined parts of outstanding high-temp. corrosion resistance and high-temp. strength and high reliability are formed. |
