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

[0010]To reach the purpose of zinc or aluminum alloy surface treatment without nature pollution and health harm, a method is provided to an alloy surface treatment which obtains an imitated hexavalent-chromium appearance and further enhances the corrosion ability of the alloy surface. The method to the environment is more eco-friendly because the poison materials, such as cyanide, used in the conventional ways are able to be replaced.

[0011]The surface treatment includes: dewaxing and deoiling to an alloy surface by using of a hydrogen-carbon vacuum cleaning (no water waste); sealing holes on the alloy surface with an organic material; forming a first coating on the alloy surface with an UV curing material; providing a plasma treatment to activate the alloy surface, then providing a physical vapor deposition process to form a second coating outside the alloy; forming a third coating on the alloy surface with another UV curing material which further comprises a toner therein, then forming a fourth coating on the alloy surface with the UV curing material. In the convention way, the healthy, harmful cyanide is commonly used for plating, however it is no need in the invention because the coating and cleaning process of the invention is carrying out in a dry way, accordingly the water waste is able to be avoided.

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.