Preparation method of high-temperature oxidation resistant TiAl3-Al composite coating on surface of titanium alloy

Abstract

The invention relates to the technical field of material research and application, particularly to a preparation method of a high-temperature oxidation resistant TiAl3-Al composite coating on the surface of a titanium alloy. The preparation method of the high-temperature oxidation resistant TiAl3-Al composite coating on the surface of the titanium alloy comprises the steps of spraying gas atomization powder, namely, pure Al powder; adopting a TC4 titanium alloy as a matrix, chamfering the two ends of the matrix, carrying out ultrasonic cleaning, sand blasting roughening, surface purging and spraying on the matrix, and preparing a pure Al layer; and putting a sample with the pure Al coating into a tube furnace to be subjected to vacuum thermal diffusion treatment, and after keeping the temperature of 610 DEG C for 8 h, carrying out furnace cooling to the room temperature, so as to obtain the TiAl3-Al composite coating. According to the preparation method, a pure Al coating prepared through low-temperature supersonic speed flame spraying is relatively compact in structure but has a small amount of micro cracks and air holes; after thermal diffusion treatment, TiAl3-Al phases are generated between the pure Al layer and the TC4 titanium alloy matrix, and a small amount of air holes exist in an interface between a TiAl3 layer and the pure Al layer; and the composite coating enters the steady oxidization stage after 5 hours of static oxidation at the temperature of 700 DEG C.

Description

technical field [0001] The invention relates to the technical field of material research and application, in particular to an alloy surface anti-high temperature oxidation TiAl 3 -Preparation method of Al composite coating. Background technique [0002] Due to its low density, high specific strength, high specific stiffness, corrosion resistance, high temperature mechanical properties, fatigue resistance and creep properties, titanium alloys are widely used in petrochemical, marine development, aerospace and other fields, especially in in aircraft engines. At present, in foreign advanced aero-engines, the amount of high-temperature titanium alloys has accounted for about 1 / 3 of its total mass. High temperature components such as stage compressor blades and turbine discs must be made of superalloys. [0003] Studies have shown that it is difficult to obtain titanium alloys that meet the service temperature above 600 °C and the requirements for creep resistance and strength...

AI Technical Summary

Problems solved by technology

The coating is prepared by the coating method, which is easy to cause penetrating cracks in the coating during the cooling process; while the coating is prepared by the magnetron sputtering method, its production efficiency is low and the cost is high; although cold spraying is suitable for spraying heat-sensitive materials Powder and matrix, but it has high requirements for equipment and requires special booster equipment, which limits its application in engineering to a certain extent.