Die casting is a process that is characterized by forcing molten metal under high pressure into a mold cavity. The mold cavity is created using two hardened tool steel dies which have been machined into shape and work similarly to a plastic injection mold during the process. This casting process is an ideal method for making a large quantity of small- to medium-sized castings with a very good surface finish and dimensional consistency.
Typical materials used in die casting
• Zinc
• Copper
• Aluminum
• Magnesium
• Lead
Advantages of die casting
• Excellent dimensional accuracy (dependent on casting material, but typically 0.1 mm for the first 2.5 cm (0.004 inch for the
first inch) and 0.02 mm for each additional centimeter (0.002 inch for each additional inch).
• Smooth cast surfaces (Ra 1.6–6.3 micrometres or 0.06–0.25 thou rms).
• Thinner walls can be cast as compared to sand and permanent mold casting (approximately 0.75 mm or 0.030 in).
• Reduces or eliminates secondary machining operations.
• Rapid production rates.
• Casting of low fluidity metals.