Aluminum casting is an important metal processing process that is widely used in automotive, aerospace, electronics and machinery fields. Its main processes include sand casting, metal mold casting, die casting, low pressure casting and investment casting.
Sand casting uses sand molds as molds. The process is simple and low-cost. It is suitable for the production of aluminum castings of various shapes and size. However, the surface roughness is high and requires subsequent processing. Metal mold casting, also known as hard mold casting, uses metal molds to produce aluminum castings with smooth surfaces and high precision. It is suitable for large-scale production with high quality requirements, but the cost is high. Die-casting and low-pressure casting use machines to inject aluminum liquid into molds, which can efficiently produce high-precision aluminum castings, and the cost is also high. Investment casting uses investment molds as molds and is suitable for the production of aluminum castings with high precision and high quality requirements.
In terms of performance, the casting process properties of aluminum alloys are mainly reflected in aspects such as fluidity, shrinkage, airtightness, casting stress and air intake. Fluidity determines whether the alloy can cast complex castings, which is affected by the composition, temperature and solid phase particles in the alloy liquid. Shrinkage is the main characteristic of cast aluminum alloys, which affects the shrinkage cavity size, stress generation, crack formation and size change of castings. Airtightness characterizes the density and purity of the internal structure of the casting, and is related to the properties of the alloy and the casting process. Casting stresses include thermal stress, phase transformation stress and shrinkage stress, which affect the mechanical properties and machining accuracy of castings. Air intake is the main characteristic of aluminum alloys. It easily absorbs gas and forms pinholes, reducing the airtightness, corrosion resistance and mechanical properties of castings.
The selection and optimization of aluminum casting processes are of great significance to improving production efficiency, reducing costs, and improving product quality.