What are the main methods for preparing high-silicon aluminum alloy composite materials?

Production process of silicon aluminum alloy silicon aluminum powder

1) Melting and casting method

The smelting and casting method has simple equipment, low cost, and can realize large-scale industrial production, and is the most extensive preparation method for alloy materials. Using conventionally cast high-silicon aluminum alloys, the distribution of Si is extremely uneven, cracks are easy to occur during processing, the material has serious composition segregation, coarse grains, poor mechanical properties and other limitations, and it is difficult to perform subsequent processing such as mechanical processing. As the silicon content in the alloy increases, the problem becomes more prominent, so it is difficult to prepare high-silicon aluminum alloy materials by conventional casting.

2) Impregnation method

The impregnation method is divided into pressure infiltration method and pressureless infiltration method. The pressure infiltration method uses mechanical pressure or compressed gas pressure to make the base metal melt into the reinforcement gap, which can solve the problem of incomplete infiltration of the reinforcement material and molten metal, but the pressure system is relatively complicated , So restrict its application development

3) Powder metallurgy

The main process of powder metallurgy is to disperse a certain proportion of aluminum powder, silicon powder and binder uniformly, mix and shape the powder by dry pressing, injection and other methods, and finally sinter in a protective atmosphere to form a denser material. This method solves the problem of poor wettability of silicon particles with aluminum matrix and difficulty in adding silicon particles to the melt, and the material can be formed at one time with less cutting processing, which overcomes the disadvantages of difficult processing of metal matrix composite materials. However, this method is complicated in process, difficult to accurately control, and the profile is not dense, and the cost is high.

4) Vacuum hot pressing method

The vacuum hot pressing method refers to a sintering process in which pressure forming and pressure sintering are carried out at the same time. Its advantages are: ①The powder is easy to plastically flow and densify; ②The sintering temperature and sintering time are short; ③The density is high. The general process is: under vacuum conditions, the powder is placed in the mold cavity, the powder is heated while being pressurized, and a compact and uniform material is formed after a short time of pressurization. However, due to its complex process and poor operability, the application of this technology in the preparation of high-silicon aluminum alloys is limited.

5) Rapid cooling/spray deposition

The rapid cooling/spray deposition technology is a rapid solidification technology developed in order to overcome the complex process and serious oxidation problems, and to compete with powder metallurgy and other technologies. Because this process has advantages that other processes cannot match, it has developed rapidly in recent years. Rapid cooling/spray deposition has the following advantages: 1) no macro-segregation; 2) fine and uniform equiaxed crystal microstructure; 3) fine primary precipitation phase; 4) low oxygen content; 5) improved thermal processing performance.

Silicon aluminum alloy Silicon aluminum powder classification

The industrially important silicon-aluminum alloys can be divided into four categories:

(1) Hypoeutectic silicon aluminum alloy contains 9%-12% silicon.

(2) Eutectic silicon aluminum alloy contains 11% to 13% silicon.

(3) The silicon content of hypereutectic aluminum alloy is above 12%, mainly in the range of 15% to 20%.

(4) Those with a silicon content of 22% or more are called high-silicon aluminum alloys, of which 25%-70% are the main ones, and the highest silicon content in the world can reach 80%.

Overview of silicon aluminum alloy Si-Al powder

High-silicon aluminum alloy powder is a binary alloy composed of silicon and aluminum, which is a metal-based thermal management material. High-silicon aluminum alloy materials can maintain the excellent properties of silicon and aluminum, and the content of silicon and aluminum is quite abundant. The silicon powder preparation technology is mature and the cost is low. At the same time, this material does not pollute the environment and is harmless to the human body. Why add silicon to aluminum?

When it is added to aluminum, silicon makes the metal alloy more fluid without damaging the metal at high temperatures. Silicon actually lowers the melting point of aluminum. Aluminum does not experience hot tearing because it has no brittleness.

The density of high silicon aluminum alloy is between 2.4~2.7 g/cm³, and the coefficient of thermal expansion (CTE) is between 7-20ppm/℃. Increasing the silicon content can significantly reduce the density and thermal expansion coefficient of the alloy material. At the same time, high-silicon aluminum alloy also has good thermal conductivity, high specific strength and rigidity, and has good electroplating performance with gold, silver, copper, and nickel. It can be welded to the substrate and is easy to precision processing. It is an electronic packaging material with broad application prospects, especially in high-tech fields such as aerospace, space technology, and portable electronic equipment. Tianji is the world's most reliable supplier of Si-Al powders for Si-Al alloys. Welcome to consult the latest prices of Si-Al alloys.

Application of silicon aluminum alloy Si-Al powder

1) High-power integrated circuit packaging: high-silicon aluminum alloy provides effective heat dissipation;

2) Carrier: It can be used as a local heat sink to make the arrangement of components closer;

3) Optical frame: high silicon aluminum alloy provides low thermal expansion coefficient, high rigidity and workability;

4) Heat dissipation part: High silicon aluminum alloy provides effective heat dissipation and structural support.

Application of silicon aluminum alloy Si-Al powder in auto parts

High-silicon aluminum alloy material (silicon content 20%-35%) has excellent tribological properties and can be used as an advanced lightweight wear-resistant material for various transportation vehicles, various power machinery, machine tools, special fasteners and tools. Is widely used.

High-silicon aluminum alloy has a series of advantages such as small specific gravity, light weight, good thermal conductivity, low thermal expansion coefficient, stable volume, good wear resistance, and good corrosion resistance. Widely used as cylinder liners, pistons, automobile engine rotors and brakes. Sheets and other materials.

Silicon aluminum alloy Si-Al powder price

The price of silicon aluminum alloy Si-Al powder will vary randomly with the production cost, transportation cost, international situation, exchange rate and supply and demand of silicon aluminum alloy Si-Al powder market. Tanki New Materials Co., Ltd. aims to help various industries and chemical wholesalers find high-quality, low-cost nanomaterials and chemicals by providing a full set of customized services. If you are looking for silicon aluminum alloy silicon aluminum powder, please feel free to send an inquiry to get the latest price of silicon aluminum alloy silicon aluminum powder.

Suppliers of silicon aluminum alloy Si-Al powder

As a global supplier of silicon aluminum alloy Si-Al powder, Tanki New Materials Co., Ltd. has extensive experience in the performance, application and cost-effective manufacturing of advanced engineering materials. The company has successfully developed a series of powder materials (including boron carbide, aluminum carbide, titanium carbide, etc.), high-purity targets, functional ceramics and structural devices, and provides OEM services.