Thin-walled structure with large temperature gradient and its preparation method by laser direct deposition

Abstract

The invention discloses a thin-walled large temperature gradient structural part. A thin-walled structure with a large temperature gradient, which sequentially includes a medium temperature layer, a temperature gradient transition layer, a high temperature base layer and a high temperature layer along the temperature gradient direction of the structure; wherein, the components of the temperature gradient transition layer are the medium temperature layer and the high temperature layer. A mixture of materials for the high-temperature layer, the material of the high-temperature base layer is the same as that of the high-temperature layer, and the temperature gradient transition layer and the high-temperature base layer are used to reduce the tissue stress and thermal stress of structural parts with large temperature gradients. The invention also discloses a laser direct deposition preparation method for thin-walled large temperature gradient structural parts. The invention adds a temperature gradient transition layer and a high-temperature base layer to the gradient structure of different materials, and the temperature gradient transition layer realizes a uniform and stable transition of transition layer materials, and the deposition speed of the temperature gradient transition layer and the high-temperature base layer is relatively slow, reducing the gradient structure Tissue stress and thermal stress realize the integrated forming of dissimilar materials with large temperature gradient structure.

Description

technical field [0001] The invention belongs to the technical field of special metal forming and processing, and relates to a thin-walled large temperature gradient structural part and a laser direct deposition preparation method thereof. Background technique [0002] During the high-speed flight of the aircraft, the temperature gradient of various parts is very large. For example, the temperature in the local area of ​​​​the air inlet is as high as 700 ° C to 800 ° C. It needs to be made of high temperature resistant, high strength, and high rigidity materials, while other parts have lower temperatures. Ordinary titanium alloys can meet the requirements of use. Through the integrated manufacturing of titanium alloy large temperature gradient structural parts with different properties to make them integrally formed, the temperature requirements of different parts of the parts can be achieved at a lower cost, which not only saves the connection and sealing problems of parts, ...

AI Technical Summary

Problems solved by technology

[0003] Compared with the preparation of single material materials, the preparation of large temperature gradient structural parts by laser direct deposition has its own difficulties. The preparation of large temperature gradient structural parts uses dissimilar material powders. Due to the different physical and chemical properties of the materials, the melting and solidification processes are different, which is easy to produce Harmful impurities or microcracks; in addition, for thin-walled structures, it is easier to cause structural deformation due to stress concentration caused by sudden changes in material composition and performance, affecting structural accuracy

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