Magnesium alloy PC middle frame

Part name
Magnesium alloy PC middle frame
Material
AZ91D
weight
25g
Tolerance standard
ISO 2768-mk
Production equipment
188T Die Casting Machine
Surface finish
Anodizing
Production place
Guangdong, China
service
OEM
Process route
Die casting-deburring-CNC-Anodizing
Application field
Kitchen supplies

What are the advantages of Magnesium alloy PC middle frame die-casting
1. Magnesium alloy material is light
2. Good fluidity, easy to form, the thinnest wall thickness can reach 0.3mm
3. Low density, good specific performance, good shock absorption performance, thermal and electrical conductivity, non-magnetic, good shielding and non-toxic.
4. Surface treatment: electrophoresis, spraying, coating

What are the application areas of magnesium total gold die casting？
Magnesium alloys are widely used in portable 3C products, equipment and automotive industries to achieve the purpose of lightweight.
The specific gravity of magnesium alloy is the lightest among all structural alloys. Therefore, without reducing the strength of the parts, the weight of aluminum or iron parts can be reduced. The specific strength of magnesium alloy is significantly higher than that of aluminum alloy and steel, and the specific stiffness is equivalent to that of aluminum alloy and steel. In the elastic range, when magnesium alloy is subjected to impact load, it absorbs more energy than aluminum alloy parts, so magnesium alloy has good shock resistance and noise reduction performance. Under the same load, the damping performance is 100 times that of aluminum and 300 to 500 times that of titanium alloys. The electromagnetic shielding performance is good. The shells of 3C products (mobile phones and computers) must be able to provide superior anti-electromagnetic protection, and the magnesium alloy shell can completely absorb electromagnetic interference with a frequency of more than 100db. Good texture, the appearance and touch texture of magnesium alloy are excellent, which makes the product more luxurious and less prone to corrosion in the air.Magnesium alloy has an absolute advantage in heat dissipation relative to alloys. For radiators of the same volume and shape of magnesium alloy and aluminum alloy, the heat (temperature) produced by a certain heat source is easier to transfer from the root of the heat sink than aluminum alloy. The speed to the top makes it easier for the top to reach high temperatures. That is, the temperature difference between the root and top of the radiator made of aluminum alloy material is smaller than that of the radiator made of magnesium alloy material. This means that the temperature difference between the air temperature at the root of the heat sink made of magnesium alloy and the air temperature at the top is larger than that of the heat sink made of aluminum alloy material, so it accelerates the diffusion and convection of the air inside the radiator and improves the heat dissipation efficiency. Therefore, at the same temperature, the heat dissipation time of magnesium alloy is not half that of aluminum alloy.Therefore, magnesium alloy is an ideal material for LED and other lighting, automotive application parts, and other parts that require high quality, high strength, and high toughness.What are the surface treatments of magnesium alloys?
Chemical treatment
The chemical conversion coating of magnesium alloy can be divided into chromate series, organic acid series, phosphate series, KMnO4 series, rare earth element series and stannate series according to the solution.
The chemical conversion film is thin, soft, and weak in protection, and is generally only used as an intermediate layer for decoration or protection.
Anodizing
Anodizing can obtain a better wear-resistant and corrosion-resistant coating base coating than chemical conversion, and has good bonding force, electrical insulation and thermal shock resistance. It is one of the commonly used surface treatment technologies for magnesium alloys. .
However, the anodic oxide film is brittle and porous, and it is difficult to obtain a uniform oxide film layer on complex workpieces.
Metal coating
Magnesium and magnesium alloys are the most difficult metals to be plated. The reasons are as follows:
(1) Magnesium oxide, which is easily formed on the surface of magnesium alloy, is not easy to clean up, which seriously affects the adhesion of the coating;
(2) The electrochemical activity of magnesium is too high, and all acidic plating solutions will cause rapid corrosion of the magnesium matrix, or strong substitution reaction with other metal ions, and the coating bonding after substitution is very loose;
(3) The second phase (such as rare earth phase, γ equal) has different electrochemical characteristics, which may cause uneven deposition;
(4) The standard potential of the coating is much higher than that of the magnesium alloy substrate. Any through hole will increase the corrosion current and cause serious electrochemical corrosion. However, the electrode potential of magnesium is very negative. It is difficult to avoid hydrogen evolution caused by pinholes during plating. ；
(5) The compactness of magnesium alloy castings is not very high, and there are impurities on the surface, which may become the source of pores in the coating.
Therefore, the chemical conversion coating method is generally used to dip zinc or manganese, etc., and then plate copper, and then perform other electroplating or electroless plating treatments to increase the bonding force of the coating. Magnesium alloy electroplating layer has coatings such as Zn, Ni, Cu-Ni-Cr, Zn-Ni, etc. The electroless plating layer is mainly Ni-P, Ni-W-P and other coatings.
A single electroless nickel layer is sometimes insufficient to protect magnesium alloys well. It has been studied that by combining the electroless Ni layer and the alkaline electroplating Zn-Ni coating, the coating with a thickness of about 35μm can withstand 800-1000h neutral salt spray corrosion after passivation. Some people also use electroless nickel plating as the bottom layer, and then use DC electroplating nickel to obtain a microcrystalline nickel coating. The average crystal grain size is 40nm. Due to the refinement of the crystal grains, the porosity of the coating is greatly reduced and the structure is more compact.
Electroplating or electroless plating is a surface treatment method that simultaneously obtains superior corrosion resistance and electrical, electromagnetic and decorative properties. The disadvantage is that the Cr, F and the plating solution in the pretreatment cause serious environmental pollution; most of the plating layer contains heavy metal elements, which increases the difficulty and cost of recovery. Due to the characteristics of the magnesium matrix, the binding force needs to be improved.