Method for sealing holes of micro arc oxidation film at room temperature

Abstract

The invention relates to a method for sealing holes of micro arc oxidation film at room temperature. Solution prepared with sodium silicate, nickel salt, solvent and accelerant is adopted as a sealant, after stewing for at least 2 hours, the sealant is adopted to seal the holes of micro arc oxidation film by soaking at room temperature, after sealing holes, the sealant forms an adsorption crystal packing in micro holes on the surface of the micro arc oxidation film so as to achieve hole sealing. The solvent is deionized water, and the ratio of sodium silicate, nickel salt and accelerant is as follows: 5-15 g / L of sodium silicate, 2-8 g / L of nickel salt and 0.1-2 g / L of accelerant. The sodium silicate is sodium metasilicate pentahydrate or sodium metasilicate. The nickel salt is nickel fluoride, nickel acetate or the mixture of the two. The accelerant is boric acid, thiourea, zirconium potassium fluoride or the mixture thereof. The solution of sealant provided by the invention can be used without heating, and the hole sealing can be performed at room temperature, which is easy and simple and has good hole sealing effect without any effect to the hardness of ceramic membrane. Meanwhile, the corrosion resistance of ceramic membrane can be improved.

Description

technical field [0001] The invention relates to a hole sealing method of a micro-arc oxidation film at normal temperature. Background technique [0002] Micro-arc oxidation technology is a new technology developed on the basis of hard anodizing technology. It can directly grow in situ on the surface of aluminum, magnesium, titanium, zirconium, niobium and other metals to form A series of ceramic membranes with excellent properties such as insulation and thermal shock resistance. It is widely used in aviation, shipbuilding, textile, automobile and other industries. However, in the micro-arc oxidation process, the action of the arc melts the ceramic film formed on the surface, and a large number of micron-sized pores are formed under the combined action of the gas formed on the surface of the ceramic film. These micropores exist in a large number in the ceramic film, and some micropores are connected with the metal substrate, so that the liquid can easily reach the metal sub...

AI Technical Summary

Problems solved by technology

Due to the large pore size of the micro-arc oxidation film, some holes penetrate the entire oxide film, and it is difficult to effectively seal the micro-arc oxidation film by boiling water sealing; the resin spraying and curing sealing equipment requires a lot of investment and high cost; anodic oxidation film sealing There are many types of porogens, and the corresponding micro-arc oxidation film sealing test has not been carried out, which seriously affects the quality of micro-arc oxidation film sealing

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