Metal surface treatment method 1. Anodizing: mainly anodizing of aluminum, using electrochemical principles to form a layer of Al2O3 (aluminum oxide) film on the surface of aluminum and aluminum alloys. This oxide film has special characteristics such as protection, decoration, insulation and abrasion resistance.
1. Process flow:
Single color/gradient color: polishing/sandblasting/drawing-degreasing-anodic oxidation-neutralization-dyeing-sealing-drying
Two colors: ①Polishing/sandblasting/drawing——degreasing——masking——anodic oxidation 1——anodic oxidation 2——sealing——drying; ②polishing/sandblasting/drawing——degreasing——anodic oxidation 1-laser carving-anodic oxidation 2-sealing-drying.
2. Technical features: improve strength; achieve any color except white; achieve nickel-free sealing, meeting the requirements of countries such as Europe and the United States for nickel-free.
3. Technical difficulties and key points of improvement:
The yield level of anodizing is related to the cost of the final product. The key to improving the oxidation yield is the proper amount of oxidizer, proper temperature and current density. This requires the metal surface treatment of structural parts to continue to explore and seek breakthroughs in the production process.
Metal surface treatment method two, electrophoresis: used for stainless steel, aluminum alloy, etc., can make the product show a variety of colors, and maintain the metallic luster, at the same time enhance the surface performance, with better anti-corrosion performance.
1. Process flow: pretreatment-electrophoresis-drying
2. Technical features:
(1) Advantages: rich colors; no metal texture, can be used with sandblasting, polishing, wire drawing, etc.; processing in a liquid environment can achieve surface treatment with complex structures; mature technology and mass production.
(2) Disadvantages: The ability to hide defects is average, and the pretreatment of die-casting parts for electrophoresis is relatively high.
Metal surface treatment 3. Micro-arc oxidation: The process of applying high voltage in the electrolyte to form a ceramicized surface film. This process is the result of the synergistic effect of physical discharge and electrochemical oxidation.
1. Process flow: pretreatment-hot water washing-MAO-drying
2. Technical features:
(1) Advantages: ceramic texture, dim appearance, no high-gloss products, delicate touch, anti-fingerprint; multiple substrates: Al, Ti, Zn, Zr, Mg, Nb and their alloys, etc.; simple pretreatment, excellent corrosion resistance Resistance and weather resistance, good heat dissipation performance.
(2) Disadvantages: The current colors are limited, only black and gray are more mature. It is currently difficult to obtain bright colors; the cost is mainly affected by high power consumption, and it is one of the most expensive metal surface treatment methods.