| 摘要 |
The reconditioned turbine blade (1) for the rotor (2) of a turbine, comprises a blade tip (3) comprising a crystalline base body (4) extending in radial direction, where an oxidation-resistant intermediate layer is applied on the radially outwardly located blade tip by a known laser hard surfacing layer and is bound epitaxially with the base body. A wear- and oxidation-resistant layer is arranged, which consists of oxidation-resistant binder material and abrasive particles. The intermediate layer consists of an oxidation-resistant MCrAlY alloy of gamma /beta or gamma /gamma ' type. The reconditioned turbine blade (1) for the rotor (2) of a turbine, comprises a blade tip (3) comprising a crystalline base body (4) extending in radial direction, where an oxidation-resistant intermediate layer is applied on the radially outwardly located blade tip by a known laser hard surfacing layer and is bound epitaxially with the base body. A wear- and oxidation-resistant layer is arranged, which consists of oxidation-resistant binder material and abrasive particles. The intermediate layer consists of an oxidation-resistant MCrAlY alloy of gamma /beta or gamma /gamma ' type, whose chemical composition is selected such that the gamma -phase is formed first and then the beta - and/or gamma '-phase is formed in the epitaxial solidification. The oxidation-resistant MCrAlY alloy has a solidification interval between the solid- and liquid temperature of less than 30K. The chemical composition of the oxidation-resistant MCrAlY alloy is selected such that it lies in the ternary nickel-aluminum-chromium phase diagram and/or nickel/cobalt-aluminum-chromium-phase diagram in the y-phase region and closes to the eutectic line between the gamma - and beta or gamma '-phase regions. The oxidation-resistant MCrAlY alloy consists of cobalt (35-39 wt.%), chromium (18-26 wt.%), aluminum (5-8 wt.%), yttrium (0.3-1.2 wt.%), silicon (0.1-1.2 wt.%), and nickel and cobalt (0-2 wt.%). The oxidation-resistant intermediate layer refers a material used as a binder material in the wear- and oxidation-resistant layer. The abrasive material in the wear- and oxidation-resistant layer is cubic boron nitride. The proportion of abrasive material in the wear- and oxidation-resistant layer increases in the radial direction to the outside. The turbine blade in a previous service interval of the turbine is inserted without abrasive blade tip. The turbine blade has a length (L), which is varied using the laser hard surfacing layer. An independent claim is included for a method for the production of a crystalline turbine blade. |
