| 摘要 |
A heat-resistant Ni-alloy material excellent in the resistance to the oxidation at a high temperature, characterized in that it is a Ni-ally substrate having been subjected to Al diffusion treatment, it has the substrate and, formed on the surface thereof, a surface layer having a bi-layer structure of an inner layer comprising an alphaCr phase and an outer layer comprising a beta phase (Ni-Al-Cr) and a gamma' phase (Ni3Al(Cr)), and the outer layer has an Al concentration of 20 atomic % or more. The alphaCr phase functions as a barrier layer for diffusion. The outer layer having a high Al concentration secures a high Al concentration which is required to repair defects of an Al2O3 film generated by damages caused due to conditions whereunder the material is used, and allows the duration of excellent high temperature characteristics inherent in a Ni alloy for a long period of time. The heat-resistant Ni-alloy material is suppressed in the corrosion at a high temperature and abnormal oxidation and is excellent in the duration of excellent high temperature characteristics inherent in a Ni alloy, and thus can be suitably used for high temperature applications such as for a gas turbine, a jet engine and a member for an exhaust gas. |
