Aluminum castings have a wide range of weight and size. The light weight is only a few grams, the weight is 400 tons, the thickness of the thin wall is only 0.5 mm, the thickness of the thin wall is more than 1 meter, and the length is from a few millimeters to more than ten meters, which can meet different industries. The use requirements of the department. Generally, for the appearance quality of aluminum castings, the surface roughness of aluminum castings can be judged by comparing samples, and the fine cracks on the surface can be inspected by the coloring method and the magnetic powder method. The internal quality of aluminum castings can be inspected and judged by audio, ultrasonic, eddy current, X-ray and γ-ray methods.

The quality of aluminum castings has a great influence on the performance of mechanical products. For example, the impeller, casing and cavity size, profile accuracy and surface roughness of various pumps directly affect the working efficiency, energy consumption and cavitation development of the pump and hydraulic system, while the cylinder block, cylinder head, and cylinder liner of internal combustion engine Piston rings and exhaust pipes directly affect the service life of the engine.

Principles for choosing casting methods for aluminum castings: Sand casting is preferred for aluminum castings, mainly because sand casting is cheaper than other casting methods, the production process is simpler, and the production cycle is shorter. When the wet mold does not meet the requirements, consider using a clay sand surface dry sand mold, dry sand mold or other sand molds. The casting method of aluminum castings should be compatible with the production batch. Casting methods such as low pressure casting, die casting and centrifugal casting are only suitable for mass production due to the expensive equipment and molds. Aluminum castings can be cast in single pieces or mass-produced.

Shrinkage porosity of cast aluminum generally occurs in thick parts at the root of the fly riser near the inner runner, the wall thickness transition part and the thin wall part with a large flat surface. In the as-cast state, the fracture is gray, and the light yellow is grayish-white, light-yellow or gray-black after heat treatment.