Preparation method of scale type aluminum zinc powder using high-energy ball milling

Abstract

A method for preparing scale type zinc-aluminium powder by wet high energy ball milling comprises the following working procedures: (1) ball milling; (2) primary suction filtration; and / or (3) pasty product packing; (4) cleaning; (5) secondary suction filtration; (6) baking; (7) dispersion; and / or (8) dry powdery product packing.

Description

technical field [0001] The invention relates to a method for preparing scale-type zinc-aluminum powder by high-energy ball milling. Background technique [0002] Zinc-rich paint is the most widely used antirust primer in the field of steel structure corrosion protection and shop primer field. However, the zinc-rich coatings actually used in domestic and foreign projects all belong to spherical zinc coatings, that is, all use spherical zinc powder as a filler. In the nodular zinc coating, in order to pursue a high dry film zinc content to ensure the conductivity and service life of the coating, the addition of zinc powder in the slurry is as high as 80%. Adding such a large amount of zinc powder has greatly exceeded the critical volume concentration (CPVC) of the filler. At this time, the amount of binder in the slurry is not enough to fill the pores between the nodular zinc particles, which leads to the porosity of the coating structure, large porosity and poor shielding p...

AI Technical Summary

Problems solved by technology

The invention patent application with the publication number CN1369338A discloses a method for preparing scaly metal powder by wet grinding. The method includes a sorting process, which requires special sorting equipment. It is a single scaly metal powder

[0007] More importantly, during the ball milling process of the scale-type zinc powder involved in the above patents and documents, due to the addition of ball milling aids, mainly stearic acid, zinc stearate, sodium dodecylbenzenesulfonate, etc. Ball milling aid, the surface of the produced scaly zinc powder is also firmly attached to a layer of this type of ball milling aid, even if there is a coating process of scaly powder in the next process, this type of ball milling aid cannot be removed

Because this kind of ball milling aid will react with silicate ball milling aid, if the scaly zinc-aluminum powder without ball milling aid is used in water-based zinc-rich coatings, it will lead to the failure of water-based zinc-rich coatings

Therefore, the scale-type zinc powder produced by domestic and foreign flake-type zinc powder preparation technologies cannot be used for water-based zinc-rich coatings, which is why other manufacturers at home and abroad can only produce solvent-based scale-type epoxy zinc-rich coatings, but cannot develop water Causes of permanent flake type zinc-rich coatings

[0008] In addition, due to the scale-type zinc powder produced by domestic and foreign technologies, a single zinc powder raw material is used, and there is no scale-type zinc-aluminum alloy powder formed by mechanical alloying of spherical zinc powder and spherical aluminum powder through high-energy ball milling.

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