Aluminum-silicon alloy, also called aluminum-silicon or aluminum-silicon. It has good casting performance and wear resistance, small thermal expansion coefficient, the largest variety in casting aluminum alloy, the largest amount of alloy, silicon content in 10% ~ 25%. Sometimes add 0.2% ~ 0.6% magnesium silicon aluminum alloy, widely used in structural parts, such as shell, cylinder, box and frame. Sometimes the mechanical properties and heat resistance of the alloy can be improved by adding appropriate amount of copper and magnesium. Such alloys are widely used to make parts such as pistons.
The alloy containing 4.5% ~ 5.3% COPPER has the best strengthening effect, and the appropriate addition of manganese and titanium can significantly improve the strength and casting properties at room temperature and high temperature. It is mainly used to make sand castings which can bear large dynamic and static loads and have uncomplicated shapes.
Aluminum-magnesium alloy, the cast aluminum alloy with the smallest density (2.55g/cm3) and the highest strength (about 355MPa), containing 12% magnesium, has the best strengthening effect. The alloy has good corrosion resistance in air and sea water, good comprehensive mechanical properties and machinability at room temperature, and can be used as radar bases, engine casings, propellers, landing gear and other parts of aircraft, as well as decorative materials.
In order to improve the properties of aluminum and zinc alloys, silicon and magnesium elements are often added, often called zinc-silicon aluminine. Under the casting condition, the alloy has quenching action, that is, self-quenching. It can be used without heat treatment, so that the casting has higher strength after metamorphic heat treatment. After the stabilization treatment, the size is stable, often used to make models, plates and equipment support.
