| 摘要 |
PURPOSE:To decrease deformation and to prevent the generation of stress corrosion cracking by melting the surface on the steam inflow side of a vane top and adding an alloy element thereto at the same instant to form an alloy layer, then subjecting the alloy layer to a heat treatment. CONSTITUTION:An alloy type element such as Mo foil 5 is attached to the part corresponding to the corrosion preventive piece on the steam inflow side surface of the turbine moving blade made of a Ti alloy. An electron beams 6 or the like is irradiated thereto from above to melt the same down to about 1.2mm from the surface, thus forming the alloy layer 7. Since the alloy layer 7 is considerably thinner than the thickness of the vane body 1, deformation is hardly generated. The alloy layer 7 is then hardened by a heat treatment to form the corrosion preventive layer for preventing erosion by steam. This turbine vane does not require the correction of deformation, obviates the generation of the residual stress arising from the correction and has no danger of generating the stress corrosion cracking.
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