The casting process and preparation method of aluminum castings mainly include the following steps:
Carry out smelting of aluminum or aluminum alloy. Aluminum ingots or scrap aluminum are heated to a molten state in a furnace to remove impurities and adjust alloy compositions to ensure the performance of the casting. The melting temperature needs to be controlled between 700℃ and 800℃ to prevent overheating of the aluminum liquid from causing oxidation and gas absorption.
Choose the appropriate modeling process. The molding process depends on the complexity of the casting, production batch size and cost requirements. Commonly used molding processes include sand casting, metal mold casting, pressure casting and low pressure casting. Sand mold casting is suitable for the production of castings with complex shapes and small batches; metal mold casting is suitable for mass production and has high size accuracy and surface finish.
Pour. Inject the melted aluminum liquid into the shaped mold at the set temperature and speed. The pouring temperature and speed need to be accurately controlled to avoid defects such as pores, inclusions and cold shuts. After pouring, the casting is cooled and solidified in the mold, and the cooling rate also affects the structure and properties of the casting.
After the casting is cooled and solidified, it is demolded and cleaned. To remove sticky sand, burrs, flash, etc. on the casting surface, common cleaning methods include sandblasting, shot blasting, machining, etc.
Carry out post-processing. Including heat treatment, surface treatment, etc. Heat treatment can improve the mechanical properties of castings, eliminate internal stress, and improve size stability. Surface treatments such as anodic oxidation, electroplating, etc. can improve the corrosion resistance and aesthetics of aluminum castings.
Through strict process control and technical key points, high-quality aluminum castings can be produced.