Aluminum profile surface pretreatment process

Abstract

The invention discloses an aluminum profile surface pretreatment process. The aluminum profile surface pretreatment process comprises the following steps: (S01) degreasing, namely placing a to-be-treated aluminum profile in circularly-flowing degreasing liquid, wherein the temperature of the degreasing liquid is 35 to 40 DEG C and the degreasing time is 0.5 min to 3 min in a treatment process; (S02) performing alkaline soaking, namely soaking the aluminum profile in pre-treating liquid for 1 s to 2 s, wherein the pre-treating liquid consists of the following components: 15 wt% to 20 wt% of sodium hydroxide, 5 wt% to 10 wt% of sodium nitrate, 5 wt% to 10 wt% of sodium phosphate, 2 wt% to 3 wt% of anhydrous nickel dichloride and the balance of water, and the temperature of the pre-treating liquid is 90 to 95 DEG C; (S03) performing primary corrosive washing, namely stewing the aluminum profile which is subjected to the primary corrosive washing in primary corrosive washing liquid; and (S04) performing secondary corrosive washing, namely placing the degreased aluminum profile in circularly-flowing secondary corrosive washing liquid. The aluminum profile surface corrosive washing process provided by the invention is simple, feasible, low in cost and capable of being stably used for a long time; moreover produced waste water and waste liquid can be treated quietly easily, and the influences on the environment are small. The aluminum profile surface pretreatment process disclosed by the invention is especially applicable to an aluminum profile of which the surface pollution is relatively serious and an oxidation film is larger than 0.2 mm in thickness.

Description

technical field [0001] The invention belongs to the technical field of aluminum alloy processing, and in particular relates to a surface pretreatment process of aluminum profiles. Background technique [0002] Aluminum alloy profiles need to be surface treated before they are used as finished products, the purpose of which is to solve or improve the three problems of corrosion resistance, decoration and functionality of the material. The corrosion potential of aluminum is relatively negative, and the corrosion is relatively serious. Therefore, protective organic polymer coatings, anodic oxidation films and other common surface treatment methods are commonly used for surface protection. In the process of spraying, anodizing, electroplating, or more refined processing, such as micro-arc oxidation, electrostatic spraying and other processes, it is very important to carry out a suitable pretreatment process on the surface of aluminum alloy profiles. Importantly, the pre-treatme...

AI Technical Summary

Problems solved by technology

Comprehensive analysis of the above-mentioned chemical surface pretreatment process shows that the chemical treatment process is simpler and easier to perform, while the electrochemical treatment requires a higher current density for aluminum profiles, and the requirements for the electrochemical polishing fluid are very high, so it is used in actual production The medium-time cost is not only high, but also has very high requirements for operators. Due to the electricity involved, it also increases the danger in the process of processing

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