Die-casting is a metal casting process. Die-casting is a precision casting method that uses high pressure to force metal melt into a metal mold with complex shapes. Its characteristic is to use the cavity of the mold to apply high pressure to the molten metal. Molds are usually made of higher-strength alloys. This process is somewhat similar to injection molding.
The cost of casting equipment and molds is high, so the die casting process is generally only used for mass production of a large number of products. Manufacturing die-cast parts is relatively easy, which generally only requires four main steps, and the individual cost increment is very low. Die casting is particularly suitable for manufacturing a large number of small and medium-sized castings, so die casting is the most widely used one among various casting processes. Compared with other casting technologies, the die-casting surface is flatter and has higher dimensional consistency.
(1) Metal parts with complex shapes, clear outlines, thin walls and deep cavities can be manufactured. Because molten metal maintains high fluidity under high pressure and high speed, it is possible to obtain metal parts that are difficult to process by other processing methods.
(2) The dimensional accuracy of die castings is high, up to IT11-13, sometimes up to IT9, and the surface roughness can reach Ra0.8-3.2um, with good interchangeability.
(3) High material utilization rate. Due to the high precision of die-casting parts, they can be assembled and used only after a small amount of machining, and some die-casting parts can be directly assembled and used. The material utilization rate is about 60%-80%, and the blank utilization rate reaches 90%.
(4) High production efficiency. Due to the high-speed filling, the filling time is short, the metal industry solidifies rapidly, and the die-casting operation cycle speed is fast. Among various casting processes, the die casting method has the highest productivity and is suitable for mass production.
(5) Easy to use inserts. It is easy to set a positioning mechanism on the die-casting mold to facilitate insert casting of inserts and meet the local special performance requirements of die-casting parts.
The specific application areas of die castings mainly include: automobile manufacturing, internal combustion engine production, motorcycle manufacturing, motor manufacturing, oil pump manufacturing, transmission machinery manufacturing, construction, hardware, equipment, machine tools, ships, aerospace, automobiles, locomotives, electronics, computers, Electrical appliances, lamps, and many other fields.
The raw materials used in press casting are different. Die casting products can be divided into aluminum alloy casting, magnesium alloy casting, zinc alloy casting, copper alloy casting and other categories. Among them, aluminum alloy is widely used in accessories of home appliances, automobiles, electronic appliances, office equipment, machinery, etc. because of its light weight, strong wear resistance, high mechanical strength, good heat transfer and electrical conductivity, and can withstand high temperatures.
Aluminum alloy pressure casting is abbreviated as aluminum alloy die casting. It is a casting method in which molten alloy liquid is poured into a press chamber, the cavity of a steel mold is filled at high speed, and the alloy liquid is solidified under pressure to form a casting. The main characteristics of die casting that distinguish it from other casting methods are high pressure and high speed.
(1) The molten metal fills the cavity under pressure, and crystallizes and solidifies under higher pressure. The common pressure is 15-100MPa.
(2) The molten metal fills the cavity at a high speed, usually 10-50 meters per second, and some can exceed 80 meters per second, (the linear velocity of the cavity through the inner gate-the inner gate speed), so the metal The filling time of the liquid is extremely short, and the cavity can be filled in about 0.01-0.2 seconds (depending on the size of the casting).
Die-casting machine, die-casting alloy and die-casting mold are the three major elements of die-casting production, and none of them are indispensable. The so-called die-casting process is the organic and comprehensive application of these three elements to enable stable, rhythmic and efficient production of qualified castings with good appearance, internal quality, and dimensions that meet the requirements of the drawing or agreement, and even high-quality castings.
Applications of die casting productions:
Engine system die-casting parts: engine block, cylinder head, intake pipe, water pump housing, engine housing, starter housing, filter base, engine bracket, engine bracket, distributor seat, carburetor, timing sprocket cover, oil Bottom shell.
Transmission system die-casting parts: gearbox housing, clutch housing, connecting filter plate, shift fork, transmission box shift end cover.
Chassis walking system die-casting parts: beams, upper and lower walls, steering casing, brake cylinder casing, brake calipers, wheels, steering forks, etc.
Die-casting of other system components: clutch pedal, steering wheel, brake pedal, steering knuckle, engine frame, ABS system components.