Metal Surface Treatment: A Comprehensive Comparison of Different Processes and Their Advantages and Disadvantages

Application of metal surface treatment

Introduction

What Is Metal Surface Treatment?

Comparative Analysis of Different Metal Surface Treatment

• CElectroplating is a technology that uses electrolysis to attach a metal film to the surface of metal to prevent corrosion, improve wear resistance, conductivity, reflectivity, and enhance aesthetics.

• Polishing is the modification of the workpiece surface using flexible polishing tools and abrasive particles or other polishing media. For different polishing processes: rough polishing (basic polishing process), medium polishing (finishing process) and fine polishing (glazing process), choosing the appropriate polishing wheel can achieve the best polishing effect and improve polishing efficiency.

• Powder spraying uses powder spraying equipment (electrostatic spraying machine) to spray powder coating onto the surface of the workpiece. Under the action of static electricity, the powder will be evenly adsorbed on the surface of the workpiece to form a powdery coating; the powdery coating is baked at high temperature Bake leveling and solidification, turning into a final coating with different effects (different types of powder coating effects).

• Black finish treatment of metal surfaces is a common chemical process. Its purpose is to form an oxide film on the metal surface to isolate air and achieve anti-rust effect. This method mainly includes the following

  1）Alkaline oxidation method. The metal is placed in a solution containing an oxidizing agent and sodium hydroxide and treated at a certain temperature. The thickness of the oxide film obtained by this method is usually between 0.8 and 1.5 microns.

  2）Acid oxidation method. The working solution used contains phosphoric acid and oxidizing agents. This method is also called cold bluing and can be performed at room temperature. The thickness of the oxide film obtained by the acidic oxidation method can reach 3 microns, and the processing time is shorter than that of the alkaline oxidation method. However, the film obtained by this method is not a pure oxide film, but also contains phosphate, so it may not be as beautiful as the alkaline oxidation method.

  3）Fire method. The metal workpiece is heated to form an oxide film on its surface, and then quenched.

  4）Electrochemical method. The metal workpiece is placed in a container containing electrolyte, and an oxide film is formed through an electrolytic reaction.

• Electrophoresis is used for stainless steel, aluminum alloys, etc., which can make the product appear in various colors, maintain the metallic luster, and at the same time enhance the surface properties and have better anti-corrosion properties.

• Spray paint is a method of spraying paint on the surface of the product and letting it dry naturally.

• Baking paint: Apply primer and topcoat to the base material. Each time the paint is applied, it is sent to a dust-free and constant-temperature baking room for baking.

Choosing the Appropriate Surface Treatment Process

• Corrosion Resistance Requirements: Metal parts working in highly corrosive environments need a method that offers extra protection, such as electroplating.

• Wear Resistance Requirements: Parts that are frequently subjected to physical friction, like common tools or machinery components, may need surface treatments like spraying.

• Appearance Requirements: Products that require decorative or special colors, such as furniture or art pieces, may benefit from colored anodizing or spraying.

• Cost and Efficiency: Parts produced in small batches or individually might suit lower-cost methods like spraying; mass production may prioritize speed and efficiency.

Conclusion