Different types of surface treatment

author: YITECH

2025-03-11

Surface treatment is an indispensable step in many mechanical processing processes. Simply put, surface treatment is the process of forming a covering layer on the surface of the workpiece through a certain method.

The advantage of doing so is that the surface of the product is more beautiful or the product has a stronger anti-rust and anti-corrosion effect. There are many types of surface treatment methods in production, and the prices of different types are also very different. The following will introduce the surface treatment quotation method for these types.

I. Types of surface treatment

(1) Electroplating

Electroplating is to immerse the parts to be electroplated in an aqueous solution containing deposited metal chemicals, and pass an electric current to allow the electroplated metal to precipitate and deposit on the parts. Common electroplating methods include zinc plating, copper plating, nickel plating, chrome alloy plating, etc. Sometimes blackening, bluing, phosphating, etc. are also included.

(2) Hot-dip galvanizing

This is done by immersing carbon steel in a plating tank with a temperature of 510 degrees Celsius and molten zinc. The result is that the iron-zinc alloy on the surface of the steel part gradually turns into passivated zinc on the outer surface of the product.

(3) Mechanical plating

The product surface is impacted by the particles of the plated metal, and the coating is cold welded to the surface of the product.

2. Quality inspection of surface treatment

The quality of plating is mainly measured by corrosion resistance, followed by appearance. Corrosion resistance is mainly the working environment of the wood square product, which is set as the test conditions and subjected to corrosion experiments. The quality of electroplated products is controlled from the following aspects:

(1) Appearance:

The appearance of the surface treatment is one of the standards for measuring the surface treatment of the product. The surface of the product is not allowed to have local no coating, roughness, burnt, dull, peeling, crusting and obvious stripes. Pinhole pitting, cracking, shedding and severe passivation marks are not allowed.

(2) Coating thickness:

The working life of the fastener coating in corrosive environments is proportional to its coating thickness.

The general economic coating thickness is 0.00015in-0.0005in (4-12um).
The average thickness of the hot-dip galvanized coating thickness standard is 54um, and the minimum thickness is 43um.

(3) Coating distribution:

In production, different deposition methods are used, and the way the coating gathers on the fasteners will also be different.

In general electroplating, the metal is deposited on the peripheral edge, which is not uniform, and a thicker coating is obtained at the corners. In the threaded part, the coating on the top of the thread is the last, and gradually becomes thinner along the side of the thread, with the thinnest part at the bottom of the tooth.
The coating distribution of hot-dip galvanizing is just the opposite, with thicker coatings deposited at the inner corners and the bottom of the thread.
The deposition tendency of the coating metal of mechanical plating is the same as that of hot-dip plating, but it is smoother and the thickness is much more uniform over the entire surface.

DongGuan YiTai Electronic Technologies Co.,Ltd

DongGuan YiTai Electronic Technologies Co.,Ltd is a manufacturing service provider located in Dongguan, China.

YiTai specialized in CNC turning machining and sheet metal fabrication mainly. As a member of Hung Mou Group, we focus on the overseas marketing development. And based on our parent company’s manufacturing capability and resources, YiTai also expended machining services such as die casting, injection molding, aluminum profile extrusion, 3D printing, which are committed to providing customers with one-stop purchasing services and experience.

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