Magnesium alloy die casting technology: industry applications, challenges and future trends

Magnesium alloy has gradually become an important material in aerospace, automotive, electronics and other fields due to its light weight, excellent mechanical properties, good corrosion resistance and thermal conductivity. As one of its processing technologies, die-casting process of magnesium alloy is widely used in the manufacture of precision parts by virtue of high precision, good surface quality and high production efficiency.

Basic properties of magnesium alloy

Magnesium alloy is an alloy formed by adding other metal elements (such as aluminum, zinc, manganese, etc.) with magnesium (Mg) as the matrix. Its light weight, high strength, corrosion resistance and other characteristics give it a wide potential for application in modern industry.

Lightweight: 

Magnesium alloys have a lower density and are about 33% lighter than aluminum alloys and 77% lighter than steel, and are widely used in industries with stringent weight requirements (e.g., aerospace, automotive).

High Strength: 

Although magnesium alloy is lighter, its tensile strength is higher, especially after alloying magnesium alloy, its strength is close to or exceeds that of some aluminum alloys.

Corrosion resistance: 

After appropriate surface treatment (e.g. anodizing), the corrosion resistance of magnesium alloys is better than that of aluminum alloys, with outstanding performance in some high humidity and salt spray environments.

Thermal Conductivity and Electromagnetic Shielding: 

Magnesium alloys have high thermal conductivity, which makes them suitable for application scenarios that require heat dissipation (e.g., electronic product housings). Its electromagnetic shielding properties also make it an ideal material in electronic

equipment.

Magnesium alloy die casting process

Magnesium alloy die casting is a process in which molten magnesium alloy material is injected into a metal mold and shaped by high pressure and rapid cooling. The die casting process is capable of producing magnesium alloy parts with complex shapes and high precision, which are widely used in automotive, electronics and aerospace fields.

The basic steps of magnesium alloy die casting process:

Melting and alloying: 

The magnesium alloy melting to a temperature of 400-500 ° C, and according to the required performance to add alloying elements (such as aluminum, zinc, manganese, etc.) for modulation.

High Pressure Injection: 

The molten magnesium alloy is injected at high pressure in a mold, typically applying pressures in the range of 50-100 MPa to ensure that the material completely fills the mold and fills in intricate details.

Cooling and Forming: 

The casting is rapidly cooled in the mold, typically for a few seconds to several tens of seconds, during which the material solidifies and takes shape.

Post-processing: 

After the casting is removed from the mold, processes such as deburring, finishing, and surface treatment are usually required to ensure the quality and appearance of the casting.

Common alloy types for magnesium die casting:

Advantages of magnesium die casting

Magnesium alloy die casting has significant advantages, especially in automotive, aerospace, electronics and other applications that require reduced component weight and increased strength. The following are the main advantages of magnesium alloy die casting:

Lightweight: 

Due to the low density of magnesium alloy, the weight of parts using magnesium alloy die casting can be significantly reduced. For example, magnesium alloy wheels are more than 25% lighter than aluminum alloy wheels.

High precision and complexity: 

The high fluidity of magnesium alloy makes it possible to cast complex shapes and high-precision parts, suitable for applications requiring high precision and complex structures, such as cell phone shells, automotive interiors and so on.

High production efficiency: 

Compared with the traditional casting process, magnesium alloy die casting production cycle is shorter, usually can be completed in 20 seconds casting molding, than the traditional aluminum alloy casting production cycle is faster.

Typical application areas for magnesium die casting:

Magnesium alloy die casting challenges & coping strategies

Although magnesium alloy die casting technology has many advantages, it still faces some challenges in practical application. Mainly including the material's easy oxidizability, the generation of porosity in the process and other issues.

High reactivity and susceptibility to oxidation: 

magnesium alloy is very easy to react with oxygen at high temperature, forming an oxide layer and affecting the quality of castings. For this reason, it is necessary to use inert gas protection (such as argon) in the melting process and control the melting temperature.

Porosity defects: 

magnesium alloy die casting process, the gas is difficult to discharge may lead to castings produce porosity. In order to solve this problem, it is necessary to optimize the design of the mold to ensure that the mold has enough exhaust holes to reduce the risk of porosity.

Thermal cracking problem: 

Magnesium alloys have a high coefficient of thermal expansion and are prone to thermal cracking during cooling. For this reason, the mold design needs to consider the cooling rate and thermal expansion and contraction issues, and select the appropriate alloy composition to improve the resistance to thermal cracking.

The future development trend of magnesium alloy die casting

With the progress of technology, the application areas of magnesium alloy die casting will be further expanded. Future research will focus on the following aspects:

Improve the mechanical properties of magnesium alloy: 

Through alloying and surface treatment, improve the performance of magnesium alloy in high temperature and high pressure environment, in order to meet the application of higher performance requirements.

New mold and process technology: 

Research on new mold design and improved die-casting technology to solve the problem of porosity, cracks and other defects, improve production efficiency and product quality.

Recyclable and environmental protection: 

With the increasingly strict environmental regulations, magnesium alloy recycling and environmental friendliness will become an important research direction. By improving the recycling rate of magnesium alloy, we can reduce the energy consumption in the production process and promote sustainable development.

Conclusion

Magnesium alloy die-casting technology has excellent characteristics such as light weight, high strength, corrosion resistance, etc., and is widely used in automotive, aerospace, electronics and other fields. Although there are some challenges in the production process, with technological progress and process optimization, the application of magnesium alloy has a broad prospect. In the future, with the emergence of more advanced alloy materials and die-casting technology, the role of magnesium alloy in lightweight and high-performance products will become more and more important.

EATHU Foundry is committed to providing high-quality casting solutions, specializing in die casting technology for light metal materials such as magnesium alloys and aluminum alloys. With advanced production equipment and a superb technical team, we provide customers with a full range of services from design to production, to ensure that each product meets strict quality standards.EATHU Foundry has accumulated rich experience in a variety of industries such as automotive, aerospace, electronics and consumer goods, and is committed to promoting the application of lightweight, high-strength, high-performance and innovative materials. We adhere to the customer's needs as the guide, continue to optimize the production process, and strive to provide each customer with efficient, environmentally friendly and sustainable casting solutions.