Alloy powder, preparation and coating for the inner surface of the upper transition zone of cement rotary kiln

Abstract

The invention discloses an alloy powder for the inner surface of a transitional zone on a rotary cement kiln and a preparation method of the alloy powder, as well as a coating prepared by the powder material. The powder material comprises the following chemical ingredients by weight percent: 30-35% of Fe, 15-20% of Co, 15-20% of Cr, 15-20% of Mn, 15-20% of Ni, and 0.004-0.008% of B. The alloy powder for the inner surface of the transitional zone on the rotary cement kiln is high in degree of sphericity, excellent in mobility, low in oxygen content, high in tap density and even in component, and is formed by a solid solution phase with a simple face-centered cubic structure. The preparation method is a one-step method low in environmental pollution and overcomes the shortcomings that a two-step method is complicated in step and high in energy consumption. The coating for the inner surface of the transitional zone on the rotary cement kiln is obtained through the cold spraying process and has excellent corrosion resistance.

Description

technical field [0001] The invention relates to the technical field of metal powder materials and material surface treatment and strengthening, in particular to an alloy powder for the inner surface of an upper transition zone of a cement rotary kiln, a preparation method thereof, and a coating prepared by using the alloy powder. Background technique [0002] The cylinder of the cement rotary kiln is the basic component for the efficient operation of the equipment. Its material is basically ordinary steel. High-temperature oxidation corrosion is common at high temperatures, resulting in an oxide layer; in addition, the atmosphere of the cement kiln contains SO 2 , Cl, K 2 O, Na 2 Harmful components such as O will also corrode the cylinder body, especially in the area of ​​the upper filter belt without kiln skin (about 25-40m, different kiln types), and the corrosion of this part of the cylinder body is serious, and the surface of the refractory brick is replaced every time ...

AI Technical Summary

Problems solved by technology

However, due to the differences in thermal physical properties such as density, melting point, specific heat and expansion coefficient between different types of metal elements in pre-mixed high-entropy alloy powders and between them and the matrix, it is directly applied to laser melting, thermal spraying, etc. On the one hand, surface technology is difficult to obtain a coating with uniform composition, and the molding quality and surface continuity of the coating cannot meet the requirements of production and use; The alloy coating is not necessarily the nominal high-entropy alloy category

[0004] Chinese patent CN103394685B discloses an alloy used to prepare high-entropy alloy coatings. It is applied to surface technologies such as laser melting and thermal spraying. On the one hand, it is difficult to obtain a coating with uniform composition, and the forming quality and surface continuity of the coating cannot meet production Requirements for use; on the other hand, in the powder and its preparation method and application: firstly, weigh various raw material powders with a particle size of not more than 200 mesh and not less than 300 mesh in proportion, put them in a mortar and grind them for 1 to 3 hours to make them fully mixed , and then carry out laser cladding modification on the surface of the iron substrate; a series of patents CN104141085A, CN104141084A and CN105401042A applied by Tianjin University also all use a mortar to grind various mixed powders to prepare alloy powders, and then in different Preparation of different coatings on the substrate by laser cladding

This method uses two-step method (preparing high-entropy alloy ingots first, and then atomizing powders) to prepare alloy powders. The steps are complicated and the energy consumption is high, and the surface of the high-entropy alloy matrix prepared in the first step is easy to form a layer of oxide film

Images