Coating improving oxidation resistance of TiAl alloy and preparing method of coating

Abstract

The invention relates to a coating and a preparing method thereof, in particular to a coating improving oxidation resistance of TiAl alloy and a preparing method of the coating. The coating improving oxidation resistance of TiAl alloy comprises an AlSiY bottom layer and a YSZ ceramic face layer, the AlSiY bottom layer is prepared through vacuum arc plating, and high-temperature diffusion and wet grit blasting treatment is carried out. The YSZ ceramic face layer of a columnar crystal structure is prepared through an electron beam physical vapor deposition method, and a typical columnar crystal structure is presented. The interfacial compatibility of the coating improving oxidation resistance of TiAl alloy and TiAl alloy is good, the oxidation resistance is superior, and the strain tolerance is high.

Description

technical field [0001] The invention relates to a coating and a preparation method thereof, in particular to a coating for improving the oxidation resistance of a TiAl alloy and a preparation method thereof. Background technique [0002] TiAl alloy has the advantages of low density, high elastic modulus and good high-temperature strength, and has a good application prospect in the aero-engine industry. However, its insufficient high-temperature oxidation resistance cannot meet the requirements of practical applications, so the development of high-temperature protective coatings suitable for TiAl alloys is one of the important prerequisites for its application. [0003] At present, people have developed aluminized coating, MCrAlY cladding coating, TiAlCr coating and nitride coating for γ-TiAl alloy. The above-mentioned coatings have significantly improved the oxidation resistance of TiAl alloys, but they have the following disadvantages: 1) Aluminized coatings are prone to p...

AI Technical Summary

Problems solved by technology

The above-mentioned coatings have significantly improved the oxidation resistance of TiAl alloys, but they have the following disadvantages: 1) Aluminized coatings are prone to penetrating cracks when preparing coatings, and can be oxidized along cracks during oxidation, and transverse cracks occur, affecting its Long-term oxidation performance and mechanical properties; 2) Serious interdiffusion between the coating and TiAl alloy occurs during the oxidation process of MCrAlY coating, forming a hard and brittle interdiffusion zone, which affects the long-term oxidation resistance of the coating system; 3) TiAlCr coating The target material is brittle, difficult to melt, and the coating deposition efficiency is low; figure 1 It can be observed that after oxidation for 100 hrs, there is obvious interdiffusion between the TiAl substrate and the NiCrAlY coating, forming a hard and brittle interdiffusion zone, forming cracks, and significantly damaging the mechanical properties of the substrate; 4) the nitride coating High stress and poor compatibility with TiAl alloy matrix

Images