High-toughness Fe-Al-Cr coating and preparation method thereof

Abstract

The invention relates to a high-toughness Fe-Al-Cr coating and a preparation method thereof, belonging to the field of preparation of an Fe-Al intermetallic compound. The coating thickness is 20-30 mu m, and the coating and the matrix are bonded metallurgically. The Fe content is 60-65 wt% in the coating surface, and increases to 90-95 wt% in a gradient way in the surface depth direction; the Al content is 0-5 wt% in the coating surface, increases to 20-30 wt% in a gradient way in the surface depth direction, and decreases to 0-5 wt% in a gradient way as the depth increases; and the Cr content is 30-40 wt% in the coating surface, and decreases to 0-10 wt% in a gradient way in the surface depth direction. The coating is prepared by an ion sputtering deposition technique, and uses an iron-aluminum-chromium alloy wire as a target. The target is in a net disk structure of which the diameter is 10 cm, and is composed of 4-6 wt% of Al, 15-25 wt% of Cr and the balance of Fe; the diameter of the wire is 1.0-1.5 mm; and the pore size of the net material is 10-14 meshes. The coating provided by the invention has high toughness, and the toughness decreases in a continuous gradient in the surface depth direction without any abrupt point in the period.

Description

technical field [0001] The invention belongs to the field of preparation of Fe-Al intermetallic compounds, and in particular relates to a high-toughness Fe-Al-Cr coating and a preparation method thereof. Background technique [0002] Fe-Al intermetallic compounds have excellent properties of high temperature oxidation resistance, corrosion resistance and wear resistance. At the same time, it has the advantages of low cost and low density. However, due to its unique long-range ordered structure, dislocation movement and atomic diffusion are difficult, and it is affected by environmental hydrogen embrittlement, resulting in poor room temperature plasticity and brittle fracture during use, which limits its application in the engineering field. Applications. Studies have shown that Cr is the most effective element to improve the toughness of Fe-Al intermetallic compounds. The reason is: Cr can not only improve the strength and hardness of the material, but also improve the pl...

AI Technical Summary

Problems solved by technology

However, the disadvantages of using this technique to prepare the resulting coatings are: During the spraying process, the powder is in contact with oxygen, which makes the coating There are large particles such as Cr2O3 and Al2O3, resulting in poor toughness of the material; It also results in porosity in the coating that must be sealed and mechanically finished to obtain a smooth surface finish; Using this technique to prepare coatings During the layering process, a large amount of dust, odor, noise and strong light radiation will be generated, which will cause serious health and safety problems for operators

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