effect of silicon in aluminium alloy

Silicon is the main element in most commonly used cast aluminum alloys. It is the main component that improves the fluidity of the alloy, with a general content of 6.5%-13%. Silicon and aluminum form a solid solution. At 577°C, the solubility of silicon in aluminum is 1.65%, at room temperature it is 0.2%, and when the silicon content reaches 11.7%, silicon and aluminum form a eutectic. Improve the high-temperature moldability of the alloy, reduce the shrinkage rate, and have no tendency of hot cracking. Binary aluminum-based alloys have high corrosion resistance. When the silicon content in the alloy exceeds the eutectic component, and there are too many impurities such as copper and iron, hard spots of free silicon will appear, making cutting difficult. High-silicon aluminum alloys will have a serious corrosion effect on the casting crucible.

1. The role of silicon in aluminum alloys

Silicon is one of the widely used alloying elements in aluminum alloys and can play many important roles. details as follows:

①. Enhance material hardness: Silicon can form a certain number of hard crystals in aluminum alloys, and these hard crystals can effectively increase the hardness and strength of the material.

②. Improve wear resistance: Silicon can make alloy materials more wear-resistant, improving the durability and service life of the material.

③. Improve corrosion resistance: Silicon can make the alloy more stable and reliable in harsh environments by improving its corrosion resistance.

④. Improve heat treatment performance: After casting and processing, silicon can improve the properties of alloy materials through heat treatment and increase the hardness and strength of the material.

2. The influence of silicon on the properties of aluminum alloys

The content of silicon in aluminum alloys will directly affect the properties of the alloy. details as follows:

①. The silicon content has an important impact on the hardness and strength of the material. Controlling the silicon content can make the material more uniform and improve the mechanical strength and durability of the material.

②. The silicon content also has an important impact on the processing performance and weldability of the material. Too high or too low silicon content may make the material difficult to process and weld.

③. The silicon content also affects the corrosion performance of aluminum alloys. Controlling the silicon content can make the alloy material more corrosion-resistant.

④. The silicon content also affects the heat treatment properties of aluminum alloys. Too high or too low silicon content will reduce the material's response to heat treatment.

Summarize

Silicon plays an important role in aluminum alloys. It can improve the hardness, wear resistance, corrosion resistance and heat treatment properties of alloy materials. For the design and manufacturing process of aluminum alloys, it is crucial to reasonably control the silicon content so that the alloy materials can have excellent mechanical properties and good stability.

Of course, the more silicon content, the better. When the silicon content of the cast aluminum alloy exceeds 14%, silicon and aluminum form a hypereutectic. If there are many impurities in the alloy, hard spots of free silicon will appear, making the cutting difficult. Difficult to process.

High silicon cast aluminum alloy will seriously corrode the crucible.