Water base non-chrome zinc-aluminium coating and methods for preparing and using same

Abstract

The invention relates to a water base non-chrome zinc-aluminium coating and methods for preparing and using the same. The coating is prepared by proportionally mixing a component A and a component B; the component A contains 50-150g / L of lamellar metal powder, 145-290ml / L of organic solvent, 10-200ml / L of deionized water, 10-36ml / L of reducing agent and 5-15ml / L of wetting agent; and the component B contains 60-240ml / L of deionized water, 20-75ml / L of binding agent, 8-22ml / L of thickening agent, 4-8ml / L of silicon compound and the balance of the organic solvent. The method for preparing the water base non-chrome zinc-aluminium coating comprises the steps of: weighing the lamellar metal powder proportionally to be mixed uniformly, and then adding the organic solvent to be mixed uniformly for later use; mixing the reducing agent with the wetting agent, adding an appropriate amount of the deionized water to be mixed uniformly, and then adding the lamellar metal powder liquid to prepare the component A; proportionally weighing the thickening agent, the binding agent and the silicon compound, and adding the organic solvent to be mixed uniformly to prepare the component B; and mixing the prepared component A and the prepared component B according to the ratio of 2:1, and stirring unit uniform, thus obtaining the coating. The method for using the water base non-chrome zinc-aluminium coating is that the coating is coated on a part to be treated, and the baking temperature is increased to 360 DEG C so as to solidify and crosslink the coating to form a dense protective layer. The coating has the corrosion resistance which reaches 840 hours of a neutral salt spray test and over 96 hours of a heat resistance test, the usage amount of harmful substances is greatly reduced, and the working environment is improved.

Description

technical field [0001] The invention belongs to the technical field of metal surface anticorrosion treatment, and relates to a water-based chrome-free zinc-aluminum coating and a preparation method thereof. Background technique [0002] With the introduction of Dacromet from Japan to my country by the Ministry of Aviation Industry in 1993, the zinc-aluminum-chromium film (commonly known as Dacromet film) technology began to be applied and developed in China. Because Dacromet technology has the advantages of no hydrogen embrittlement, less pollution, and good corrosion resistance, in 1996, the Ministry of Machinery Industry listed Dacromet as a key funding development project for clean production. In 1999, Dacromet was listed by the State Environmental Protection Administration as a National key environmental protection and practical technology, now it has become a hot spot recommended by the electroplating and coating industry around the world. [0003] However, with the im...

AI Technical Summary

Problems solved by technology

However, the implementation described in this technology requires the addition of a defoamer, indicating that the formulation will generate a large number of air bubbles during the implementation process, which will cause poor sealing of the coating film, and the air bubbles will easily lead to coating film defects, thereby affecting anti-corrosion performance

[0006] In view of the above, the research on chrome-free zinc-aluminum anti-corrosion coatings needs to be further developed