Method of manufacturing an oxidation-resistant component of a molybdenum base alloy

Abstract

The present invention relates to a method of producing a component of an Mo base alloy which is protected against high-temperature oxidation, and a correspondingly produced component.The method comprises:provision of a semifinished part composed of a Mo base alloy,provision of an Si-containing slip or of a Si-containing powder,application of the slip to the semifinished part and diffusion annealing of the semifinished part together with the applied slip to form a Si-containing outer layer ortransfer of at least part of the silicon present in the powder via the gas phase to the semifinished part by means of a diffusion heat treatment of the semifinished part together with the Si-containing powder which is arranged at a distance from the semifinished part.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]The present application claims priority under 35 U.S.C. § 119 of German Patent Application No. 102018215313.2, filed Sep. 10, 2018, the entire disclosure of which is expressly incorporated by reference herein.BACKGROUND OF THE INVENTION1. Field of the Invention[0002]The present invention relates to a method of improving the high-temperature oxidation resistance of molybdenum-based alloys or molybdenum base alloys. In addition, the present invention relates to a correspondingly produced component composed of a molybdenum base alloy which can, in particular, be a component of a turbomachine and in particular an aircraft engine.2. Discussion of Background Information[0003]Molybdenum and its alloys are interesting materials for high-temperature applications because of the high melting point and the good corrosion resistance. However, in order to avoid high-temperature oxidation it is necessary to enrich at least the surface regions of a corre...

AI Technical Summary

Benefits of technology

The patent text describes a method for transferring silicon into a semiproduct by using a silicon-containing powder that can be mixed with other constituents to improve its performance. These additional constituents can serve as filler material, prevent caking of the powder, and control the gas-phase activity of silicon. The silicon-containing powder can be placed in a ceramic vessel underneath the semiproduct during the diffusion heat treatment. Additionally, the patent describes the use of particles like oxide, carbide, or nitride to reduce viscosity and prevent running-off of an oxide layer on the component. These additional components can include aluminum oxide, zirconium oxide, and more. Overall, the patent provides technical solutions to improve the transfer of silicon into semiproducts during heat treatment processes.

Problems solved by technology

However, the known powder pack method has the disadvantage that it requires very long processing times. Furthermore, caking of the powder particles which surround the component can occur in the diffusion heat treatment, with the result that the component has to be released from a solid shell after the corresponding diffusion heat treatment, which can lead to damage to the component.

In addition, the removal of the caked silicon-containing powder is time-consuming.

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