Machining surface treatment is an important process in machining. Machining surface treatment can protect and beautify the workpiece. In machining, there are various forms of surface treatment for machining. During machining, it is necessary to correctly select the type of surface treatment according to the material and processing requirements of the workpiece.
Common types of surface treatment for machining mainly include Electroplating, nickel plating, titanium plating, gold plating, silver plating, aluminum anodizing, infiltration, oil injection, sandblasting, DLC treatment, Teflon treatment, black dyeing, cold plating, etc. Here we introduce several common types of surface treatment and their functions.
1. Electrostatic spraying
Electrostatic spraying uses the action of a high-voltage electrostatic field to move the coating particles with the floating-point in the opposite direction of the electric field and adsorb the coating particles on the workpiece surface.
A thick coating can be obtained by electrostatic spraying at one time. The powder coating has no solvent and pollution, and the labor hygiene conditions are improved. New processes such as powder electrostatic spraying are adopted, which have high efficiency, Good performance, and suitable for automatic assembly line production, and can be recycled. It has been widely used in the automotive process, electrical insulation, corrosion-resistant valves, chemical pumps, and castings.
2. Zinc, chromium, nickel, titanium, and silver plating
These surface treatment methods are to coat a layer of metal film on the surface of the Workpiece to achieve the required purpose.
(1) Galvanizing: Galvanizing refers to the surface treatment technology of plating a layer of zinc on the surface of the metal, alloy, or other materials for aesthetic and rust prevention.
(2)Chrome plating: it can make metal products more durable. Hard chromium plating is mainly used for high-temperature machineries, such as molds. Decorative chromium plating is mainly to make the surface more bright and beautiful.
(3) Nickel plating: Nickel plating: is deposited on the metal surface by redox to improve corrosion resistance, wear resistance, beauty and luster.
(4) Titanium plating: it can prevent pollution, and will not produce allergic reactions in contact with the Human body. Because titanium compounds have many colors, they can increase the aesthetic effect. At the same time, titanium has, anti-alkali and anti-oxidation.
(5) Silver plating: it has two main functions, one is decorative and the other is functional. Decorative is used for oxidation resistance tests. The functionality is mainly used in the electronic industry, such as electrodes, wires, electric shocks, pole pieces, etc.
3. Aluminum anodizing
Aluminum oxidation of aluminum is mainly an electrolytic oxidation process. In this process, aluminum and aluminum surface is usually converted into a layer of oxide film, with curing, decoration, and other functional characteristics.
The aluminum anode is mainly used in two aspects: Aluminum is used outdoors to form a protective film on the surface on the aluminum surface after the anode, which can avoid oxidation and corrosion and prolong the service life. The second one is used in electronics, which can make the surface of the hard disk shell and radiator non-conductive, and protect the circuit and human body.
This is a microporous permeable sealing process. Sealing process. The sealing medium is penetrated by natural penetration, vacuum pumping, and pressurization to fill the gap. The main function is to seal the gap.
The compressed air power is used to form a jet beam to spray the sprayed material to the workpiece surface to be treated at a high speed, to change the appearance of the workpiece surface. The function of this surface treatment is to effectively improve the fatigue resistance of workpieces and increase the adhesion between workpieces and the coating, and prolong the durability of the coating film.
The common surface treatment of aluminum die casting products is plastic spraying, shot blasting, electrophoresis, etc. Aluminum dies casting is not suitable for oxidation because the density of aluminum alloy is high and the effect of oxidation is poor. Therefore, aluminum die-casting products are more suitable for plastic spraying and more beautiful.
The common surface treatment of CNC finishing products is oxidation, plastic spraying, chromium plating, etc. If it is a profile aluminum alloy, it is suitable for aluminum oxidation, because the density becomes smaller, and the overall surface aesthetics will also increase.
Chemical heat treatment
The process in which the workpiece contacts and heats with chemical substances and orders certain elements to enter the workpiece surface at high temperature is called chemical heat treatment, such as nitriding, carburizing, etc.