The Die Casting process is versatile for producing engineered metal parts by forcing molten metal under high pressure into reusable steel molds. These molds, called dies, can be designed to produce complex shapes with a high degree of accuracy and repeat-ability. Parts can be sharply defined, with smooth or textured surfaces, and are suitable for a wide variety of attractive and serviceable finishes.
Die Castings are among the highest volume, mass-produced items manufactured by the metalworking industry, and they can be found in thousands of consumer, commercial, and industrial products. Die cast parts are important components of products ranging from automobiles to toys.
Die Casting Benefits
Die Casting is an efficient, economical process offering a broader range of shapes and components than any other manufacturing technique. Parts have long service life and may be designed to complement the visual appeal of the surrounding part. Designers can gain a number of advantages and benefits by specifying die cast parts.
- High Speed Production: Die casting provides complex shapes within closer tolerances than many other mass production processes. Little or no machining is required and thousands of identical castings can be produced before additional tooling is required.
- Dimensional Accuracy and Stability: Die casting produces parts that are durable and dimensionally stable, while maintaining close tolerances. They are also heat resistant.
- Strength and Weight: Die cast parts are stronger than plastic injection moldings having the same dimensions. Thin wall castings are stronger and lighter than those possible with other casting methods. Plus, because the die castings do not consist of separate parts welded or fastened together, the strength is that of the alloy rather than the joining process.
- Multiple Finishing Techniques: Die cast parts can be produced with smooth or textured surfaces, and they are easily plated or finished with a minimum of surface preparation.
- Simplified Assembly: Die castings provide integral fastening elements, such as bosses and studs. Holes can be cored and made to tap drill sizes, or external threads can be cast.
The Die Casting Process Overview
The basic die casting process consists of injecting molten metal under high pressure into a steel mold called a die. Die casting machines are typically rated in clamping tons equal to the amount of pressure they can exert on the die. Machines sizes range from 400 tons to 4000 tons. Regardless of their size, the only fundamental difference in die casting machines is the method used to inject molten metal into a die. The two methods are hot chamber or cold chamber.
Hot chamber machines are used primarily for zinc, copper, magnesium, lead and other low melting point alloys that do not readily attack and erode metal pods, cylinders and plungers. Cold chamber machines are used for alloys such as aluminum and other alloys with high melting points. The molten metal is poured into a “cold chamber”, or cylindrical sleeve, manually by a hand ladle or by an automatic ladle. A hydraulically operated plunger seals the cold chamber port and forces metal into the locked die at high pressures.
A complete die casting cycle can vary from less than one second for small components weighing less than an ounce, to two-to-three minutes for a casting of several pounds, making die casting the fastest technique available for producing precise non-ferrous metal parts.
In addition, there are several variations on the basic process that can be used to produce casting for specific applications. One of which is squeeze casting. Squeeze casting is a method by which molten alloy is cast without turbulence and gas entrapment at high pressure to yield high quality, dense, heat treatable components.
Advantages and disadvantages
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 1–2.5 micrometres or 0.04–0.10 thou rms).
- Thinner walls can be cast as compared to sand and permanent mold casting (approximately 0.75 mm or 0.030 in).
- Inserts can be cast-in (such as threaded inserts, heating elements, and high strength bearing surfaces).
- Reduces or eliminates secondary machining operations.
- Rapid production rates.
- Casting tensile strength as high as 415 megapascals (60 ksi).
- Casting of low fluidity metals.
The main disadvantage to die casting is the very high capital cost. Both the casting equipment required and the dies and related components are very costly, as compared to most other casting processes. Therefore, to make die casting an economic process, a large production volume is needed. Other disadvantages are that the process is limited to high-fluidity metals, and casting weights must be between 30 grams (1 oz) and 10 kg (20 lb). In the standard die casting process the final casting will have a small amount of porosity. This prevents any heat treating or welding, because the heat causes the gas in the pores to expand, which causes micro-cracks inside the part and exfoliation of the surface. Thus a related disadvantage of die casting is that it is only for parts in which softness is acceptable. Parts needing hardening (through hardening or case hardening) and tempering are not cast in dies.
One-stop services of Die-casting & Custom Manufacturing in China
- State-of-the-art Die Casting Facilities : 60,000 sq. ft. die casting floor space in China, 30 die casting machines for aluminum, magnesium, and zinc;
- Get the features you need all from a single provide. In-house CNC machining allows JINGXIN Die Casting to machine any element your casting requires. The latest technology means you can expect high-quality, repeatable machining of any type. We want to be your one-stop-shop for CNC machining and die cast services.
- Post Finish : We offer a series of post finishing services for die casting parts. The finish includes painting, electroplating, printing, powder coating, anodizing, sand blasting, E-coating, polishing, and passivation;
- We are ISO 9001 certified and our customers include some of the world’s toughest. Read More Quality control in House
- Customer Service : Our highly skilled, English-speaking staff work directly with your design engineers every step of the way, from the design stage through product delivery. We own and manage the entire life cycle of a die casting manufacturing project.
What we do to make sure you would get the quality parts from JINGXIN Die Casting shop in China.
We declare here that We will be responsible for our precision Die Casting all the time.
1.100% inspection before shipping and inspection shipment report for each piece of precision Die Casting is available. (ISO quality control during the whole production).
2. We have served Volvo auto corp since 2016 as an approved precision CNC milling company in China. no complaint so far.
3. In case Any precision Die Casting that is outside tolerance and your special specification, we will remake and delivery as fast as we can; 100% free from our side.
4. For past years, JINGXIN Die Casting company has manufacturing thousands of pieces precision Die Casting components for our customers. 99.9% satisfaction feedback drives us to supply more quality precision machined parts to meet customer’s request.