The preparation methods of composite materials mainly include the following: 1) melting and casting; 2) impregnation; 3) powder metallurgy; 4) vacuum hot pressing; 5) rapid cooling/jet deposition.
1) Smelting Casting
Melting and casting method is the most widely used method for preparing alloy materials because of its simple equipment, low cost, and large-scale industrial production. Using conventionally cast high-silicon aluminum alloys, the distribution of Si is extremely uneven, cracks are easily generated during processing, and the material has serious limitations such as segregation of components, coarse grains, and poor mechanical properties, and it is difficult to perform subsequent processing such as machining. With the increase of silicon content in the alloy, the problem is more prominent, so it is difficult to prepare high-silicon aluminum alloy materials by conventional casting.
Infiltration method is divided into pressure infiltration method and pressure infiltration method. Pressure infiltration method uses mechanical pressurization or pressurized gas pressurization, so that the matrix metal melt is immersed in the reinforcement body gap, which can solve the problems of non-wetting and impregnation of reinforcement materials and metal liquids, but the pressurization system is relatively complicated. , so limit its application development