Aluminum suitable for the die casting process is die cast aluminum, usually die cast aluminum alloy. It has a high technical content of core pulling, cooling and other systems. In general, the material is delivered through a central entrance into a cavity to be cast and "injected" to form parts.
Casting is a process of metal smelting and processing, usually using the gravity of the metal in the mold for casting. But "aluminum die-casting" is not done by gravity, but by applying pressure. It's kind of like injection molding. But it has a high technical content of core pulling, cooling and other systems. In general, the material is delivered through a central entrance into a cavity to be cast and "injected" to form parts.
High pressure and high speed filling die cast aluminum mold are two characteristics of die cast aluminum. Its commonly used injection specific pressure is from thousands to tens of thousands of kPa, and even up to 2×105kPa. The filling speed is about 10~50m/s, sometimes even more than 100m/s. The filling time is very short, generally in the range of 0.01~0.2s.
Fold the advantages
1, good product quality: casting size accuracy is high, generally equivalent to 6~7, or even up to 4; Good surface finish, generally equivalent to grade 5~8; The strength and hardness are high. The strength is generally increased by 25~30% compared with sand casting, but the elongation is reduced by about 70%. Stable size, good interchangeability; Diecasted aluminum thin - walled complex castings. For example, the minimum wall thickness of zinc alloy die-casting aluminum parts can reach 0.3mm; Aluminum alloy castings up to 0.5mm; The minimum cast aperture is 0.7mm; Minimum pitch is 0.75mm.2, high production efficiency: high machine productivity, such as domestic J ⅲ 3 horizontal cold air die casting aluminum machine can die casting aluminum 600~700 times in eight hours, small hot chamber die casting aluminum machine can die casting aluminum 3000~7000 times in eight hours on average; Die casting aluminum mold has a long life, a pay die casting aluminum mold, die casting aluminum bell alloy, life can reach hundreds of thousands of times, even millions of times; Easy to realize mechanization and automation.3, excellent economic effect: due to the precision of the size of the die-casting aluminum parts, the table gloss and clean. Generally no longer mechanical processing and direct use, or the amount of processing is very small, so not only improve the metal utilization rate, but also reduce a lot of processing equipment and man hours; Cheap casting price; A combination of die cast aluminum to other metal or nonmetal materials may be used. Save assembly time and metal.
Folding defect
1. When die casting aluminum, due to the high speed of liquid metal filling cavity and unstable flow state, the general die casting aluminum method is adopted. The casting is easy to produce pores and can not be heat treated;2. It is more difficult to die cast aluminum for inner concave complex castings3, high melting point alloy (such as copper, ferrous metals), die casting aluminum model life is low;4, it is not suitable for small batch production, the main reason is that the manufacturing cost of die casting aluminum is high, the production efficiency of die casting aluminum machine is high, and the small batch production is not economic.