What is die casting?
Die casting is a metal casting process, which is characterized by applying high pressure to the molten metal using the cavity of the mold. Molds are usually made of higher-strength alloys, and this process is somewhat similar to injection molding. Most die castings are iron-free, such as zinc, copper, aluminum, magnesium, lead, tin, and lead-tin alloys and their alloys. Depending on the type of die casting, you need to use a cold chamber die casting machine or a hot chamber die casting machine.
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 type of casting processes. Compared with other casting technologies, the die-casting surface is flatter and has a higher dimensional consistency.
Based on the traditional die-casting process, several improved processes have been born, including a non-porous die-casting process that reduces casting defects and eliminates porosity. It is mainly used for processing zinc, which can reduce waste and increase the yield of the direct injection process. There are also new die-casting processes such as precision die-casting technology and semi-solid die-casting.
About the mold
The main defects that can occur in the die casting process include wear and erosion. Other defects include thermal cracking and thermal fatigue. When the mold surface has defects due to a large temperature change, thermal cracks will occur. After too many uses, the defects on the surface of the mold will cause thermal fatigue.
About die-cast metal
The metals used for die-casting mainly include zinc, copper, aluminum, magnesium, lead, tin, and lead-tin alloys. Although die-cast iron is rare, it is also feasible. More special die-casting metals include ZAMAK, aluminum-zinc alloy, and the standards of the American Aluminum Association: AA380, AA384, AA386, AA390, and AZ91D magnesium. The characteristics of various metals during die casting are as follows:
• Zinc: The metal that is the easiest to die-cast. It is economical to manufacture small parts, is easy to coat, has high compressive strength, high plasticity, and long casting life.
• Aluminum: Light weight, high dimensional stability when manufacturing complex and thin-walled castings, strong corrosion resistance, good mechanical properties, high thermal and electrical conductivity, and high strength at high temperatures.
• Magnesium: It is easy to be machined, has a high strength-to-weight ratio, and is the lightest among commonly used die-cast metals.
• Copper: High hardness, strong corrosion resistance, the best mechanical properties of commonly used die-casting metals, wear resistance, and strength close to steel.
• Lead and Tin: high density, high dimensional accuracy, can be used as special anti-corrosion parts. For public health considerations, this alloy cannot be used as food processing and storage equipment. The alloy of lead, tin and antimony (sometimes containing a bit of copper) can be used to make manual type and bronzing in letterpress printing.
Die-casting parts are no longer limited to the automobile industry and instrument industry, and gradually expanded to other industrial sectors, such as agricultural machinery, machine tool industry, electronics industry, defense industry, computers, medical equipment, clocks, cameras, and daily hardware, etc. Industry, specifically: auto parts, furniture accessories, bathroom accessories (bathroom), lighting parts, toys, shavers, tie clips, electrical and electronic parts, belt buckles, watch cases, metal buckles, locks, zippers, etc.
1. Good product quality
The dimensional accuracy of castings is high, generally equivalent to 6~7, even up to 4; the surface finish is good, generally equivalent to 5~8; the strength and hardness are higher, and the strength is generally 25~30% higher than sand casting, but it is extended The rate is reduced by about 70%; the size is stable, and the interchangeability is good; it can die-cast thin-walled complex castings.
2. High production efficiency
3. Excellent economic effect
Due to the precise size of the die-casting, the surface is smooth and clean. Generally, it is used directly without mechanical processing, or the processing volume is small, so it not only improves the metal utilization rate, but also reduces a large number of processing equipment and man-hours; the price of castings is easy; it can be combined die-casting with other metal or non-metal materials . It saves not only assembly man-hours but also metal.
The cost of casting equipment and molds is high, so the die-casting process is generally only used to manufacture a large number of products in batches, and small batch production is not cost-effective.
QY Precision has full experience in Die Casting Process, and offers different solutions to meet your need. You can choose the suitable one for your final products and market. Welcome send your 2D/3D drawings for free quotation.