Zinc-aluminum alloy flake powder and preparation method thereof

Abstract

The invention relates to zinc-aluminum alloy flake powder and a preparation method thereof. The zinc-aluminum alloy flake powder comprises the following components of, in percentage by weight, 70%-97% of Zn, 3%-30% of Al, and 2%-4% of a coating agent, wherein the contents of lead and cadmium are both less than 50 ppm, the total amount of impurities does not exceed 0.01%, the average flake diameter of the zinc-aluminum alloy flake powder is 5-20 microns, the flake thickness is 0.1-0.3 micron, and the diameter thickness ratio is 50-200. The product is used for preparing an environment-friendly chromium-free zinc-aluminum coating liquid, the coating liquid does not form gas, the viscosity change is small, the stability is good, the flake diameter of the product is small, the diameter thickness ratio of the product is large, and a compact and fine coating is prepared favorably, so that the corrosion resistance of the coating is improved, and a smooth and moist workpiece surface is obtained; and a selected binary alloy is simple in component, the salt spray resistance time of the coating can reach 1000 hours or above without adding other elements and expensive rare earth elements, the process is simple, intermediate alloy preparation and vacuum melting atomization are not needed, the selection of a surface modifier is reasonable, the product is easy to disperse in the coating, the suspension property is good, it is not easy for the coating to form gas, the stability of the coating is good, the raw material cost and the processing cost are low, and the market competitiveness of the product is high.

Description

technical field [0001] The invention relates to the field of metal powder deep processing, in particular to a zinc-aluminum alloy flake powder and a preparation method thereof. Background technique [0002] Zinc-aluminum coating technology is a new type of high-efficiency anti-corrosion technology for steel surfaces developed in China in the past two decades, including two parts: zinc-aluminum coating solution (Dacromet coating solution) preparation technology and coating technology. Dacromet coating solution is mainly composed of pure zinc flake powder, pure aluminum flake powder, emulsifier dispersant and passivator with chromic acid as raw material. It has good corrosion resistance, and the salt spray resistance time can reach more than 1000h. Pure zinc powder flake powder and pure aluminum flake powder are ordinary Dacromet (containing Cr +6 ions) are the main raw materials. In recent years, Indacromet lotion contains a large amount of toxic Cr +6 ions are restricted...

AI Technical Summary

Problems solved by technology

[0004] However, this patent needs to add other elements and expensive rare earth elements, the price is high, the production process is more complicated, and the master alloy needs to be prepared, vacuum melting and vacuum atomization are required

[0005] At the same time, pure zinc flake powder is used to produce chromium-free environmentally friendly dacromet anti-corrosion coating liquid, which has poor stability, easy to gas, rapid viscosity change, and short shelf life of the coating; relatively poor corrosion resistance, usually salt spray resistance Only 300h ~ 400h, only 1 / 3 of chromium-containing dacromet

Images