Method of alloy surface treatment

Abstract

A alloy surface treatment includes dewaxing and deoiling to an alloy surface via a cleaning process; sealing holes on the alloy surface with an organic material; forming a first coating on the alloy surface with a UV curing material; providing a plasma treatment to activate the alloy surface, then providing a PVD process to form a second coating outside the alloy; forming a third coating on the alloy surface with another UV curing material which further includes a toner therein, then forming a fourth coating on the alloy surface with the UV curing material, wherein the toner is provided to match the color of hexavalent-chromium to obtain a hexavalent-chromium imitated product.

Description

BACKGROUND OF THE INVENTION [0001]1. Field of the Invention[0002]This invention is related to an alloy surface treatment, especially for forming an hexavalent-chromium imitated appearance on the alloy surface in order to enhance the ability of anti-corrosion.[0003]2. Description of the Related Art[0004]An zinc alloy is composed of a major component, zinc, with other secondary components, such as aluminum, copper, magnesium, chromium, lead, titanium and etc., which makes the alloy have lower melting point and good malleability to be easily manufactured. For the alloy, there is a situation where the alloy has quite amounts of impurities such as lead, chromium and tin, which causes the alloy to be more rapidly decaying, easily transformed and even easily breaking. For a reason that the elements, such as lead, tin and chromium, have weak solubility in metal, the elements are possibly converged together to form a cathode or a anode within the alloy crystalline grain, where the cathode an...

AI Technical Summary

Benefits of technology

The patent provides a method for surface treatment of zinc or aluminum alloy that mimics the appearance of hexavalent-chromium and enhances its corrosion ability without using harmful substances. The method is eco-friendly and avoids water waste by using a dry process. The method includes steps of dewaxing and deoiling, sealing holes with an organic material, forming UV curing coatings, and a plasma treatment to activate the surface. A physical vapor deposition process is then used to form a second coating outside the alloy, followed by a third coating with another UV curing material that includes a toner. The invention avoids the use of harmful cyanide in plating and ensures a healthy and safe surface treatment process.

Problems solved by technology

For the alloy, there is a situation where the alloy has quite amounts of impurities such as lead, chromium and tin, which causes the alloy to be more rapidly decaying, easily transformed and even easily breaking.

However, in a process like metal casting, the metal has a good quality of dense surface, that is, no holes on the surface, but the structure under the surface is not dense enough, and once the surface is damaged to expose the sub-layer, it is hardly electroplating onto the metal surface.

To achieve the steady combination of the plating and the metal surface, a compound of copper and cyanide is used to form a pre-layer before plating, even so this kind of compound is almost prohibited in the present manufacture due to the harmful influence to the nature and the health.