Shenzhen Prolean Technology Co., Ltd.

A Brief Review: Die-casting Pros & Cons

A Brief Review: Die-casting Pros & Cons

 

Last updated 2022/06/23

Die casting is a versatile approach in manufacturing to create the needle of the injection and automotive components to the furniture structures. The first-die casting machine was the small hand-operating machine invented in 1838. It took the revolutionary step after Otto Mergenthaler created the linotype machine in 1885, the first die casting equipment open for the market

The die-casting process makes it possible to create small items to complex geometric shapes accurately. The die used in this process is made of high-quality heat-resistant steel. The die consists of two halves, one of which is movable while another one is fixed. A cavity is provided between the two. The molten metal is injected into this cavity, and high pressure is applied to the die during the process.

Die-Casting Machine

Die-casting machine

This article will explain the die-casting process in detail, including its benefits and drawbacks in manufacturing.

 

In the die casting, molten metal is injected under high pressure into a high-strength steel mold customized for each item and used for serial production. As a result, products are precisely created with repeatability. The most commonly used materials for die casting are Aluminum, Zinc, and magnesium alloys.

Types of Die-casting process

 

1.           Cold chamber Die-casting

 

The only difference between the hot-chamber and cold-chamber die casting processes is that the shot-chamber or mold is not pre-heated before forcing the molten metal into it during the cold-chamber process. The cold chamber dies casting is used for the alloys with high melting points, such as Aluminum and copper. Besides this, other ferrous metal alloys can be cast. This process requires some extra equipment for set-up, usually an outside furnace and a ladle to pour the molten metal into the machine.

2.           Hot chamber Die-casting

 

Usually, low melting point alloys such as Zinc, magnesium, tin, and lead are cast using hot chamber die casting. In the hot-chamber die casting, a piston is used to force the molten metal into the die cavity through a gooseneck and nozzle. This molten metal is held under high pressure and can reach as high as 35 MPa. Next, a burner or furnace is provided, which increases the temperature of the molten metal as the metal solidifies inside the cavity. Finally, the movable half of the die is moved, and the casting component is obtained with the help of an ejector pin.

In the die block, several passageways are made to facilitate the circulation of water and oil to cool down the die as the molten metal fills the die cavity. By circulating water and oil during the process, die life can be increased, and the process’s cycle time can be reduced.

 

Pros of the die casting process

 

Mass manufacturing from die-casting

Mass manufacturing from die-casting

The die-casting process has several benefits for the manufacturing sector. The main benefits include the following:

1.  Wide-range of working materials 

 Although zinc and aluminum alloys are the most common working material in the die-casting process that has been used on a large scale in the manufacturing industry, it supports a wide range of materials such as copper, magnesium, lead, and ferrous alloys.

 

2.  Mass productions 

The best part about the die casting is that it can be used several times once you customize the die. The high strength and heat-resistive die even can work a million times, which best suits the mass production of products and components. 

 

3.  High production efficiency 

The cycle time of die casting production is very low compared to other manufacturing and casting approaches. Depending upon the specification of components and products, it ranges from 300 to 800shots per hour. Although the cycle time for tiny parts such as zipper

Teeth can reach as high as 18,000 shots per hour.

 

4.  High-quality surface finishing and dimensional accuracy 

Most die-cast products and components can be used immediately without additional machining or surface finishing. Still, some may require minor machining to remove a slight surface imperfection created on the line where two die halves separated during the release process. Because die-casting uses pressurized molten metal, which contributes to the high rigidity and smooth surface while eliminating the risk of rough surfaces and empty space, it provides an excellent surface finish with a high degree of dimensional accuracy.

 

5.  Excellent mechanical properties 

The die casting process immediately solidifies the liquid metal under high pressure, resulting in a fine-grain crystallization structure contributing to the cast components’ high impact strength and toughness.

 

6.  Lower wall thickness limit 

Die-casting can produce complex geometrical components with thin thickness. However, unlike in metal mold and sand castings, it does not alter the dimensional accuracy for parts with small thickness. Talking about the limit, Aluminum die-casting has a lower wall thickness limit of 0.5mm, while zinc alloy has 0.3mm.

 

7.  Cost-effective method

Die casting would be a very economical casting process if the manufacturers planned to produce the components in large quantities because a single die can be reused repeatedly over an extended period. Also, since the primary working material is always in the molten form, it reduces the material consumption because there is almost 100% working material is going to be utilized to create the product. 

 

8.  Secondary material can be inserted. 

In the final cast items of many complicated mechanical systems, there are inserts or complicated fasteners. Die casting enables manufacturers to pick such features for their products as needed. As a result, it saves assembly time and money by minimizing the material cost. Finally, Here Die-casting improves the performance of parts and the whole product. 

 

 

 

Cons of the die-casting process

 

No matter how advanced the process, every manufacturing method has drawbacks for specific tasks and situations.

Now, let’s go over each con of the Die-casting process.

1.  Small batch production is not economically feasible.

For small-scale production, it is not an economically viable option. As already mentioned, the manufacturing of dies is quite expensive and can be reused thousands of times. Therefore, if the components do not need to be produced in large quantities, the production costs will be much higher. It may not be economically feasible in some cases, such as with die casting of components for wind energy systems.

 

2.  The weight limit for casting

The die-casting process has a weight limit for producing components and finished products. However, the overall quality of the casting of an item weighing less than 15 pounds may be compromised by several flaws.

 

3.  Low life of the die for high melting point alloys

Some alloys, including those made of Aluminum, copper, and ferrous metals, have a high melting point. As a result, the life of the die is shortened while casting these metals, and the die must have highly high heat-resistance properties, which can be expensive to acquire. Also, Heat deformation on the die will affect the dimensional accuracy and other qualities of casting items.

 

4.   High Initial Cost 

Because of the high cost of the dies, control unit, and other necessary equipment, die-casting is a capital-intensive process to begin. Additionally, routine equipment maintenance is required to maintain quality control and precise accuracy. It is expensive compared to other manufacturing processes such as sand casting, plastic injection, machining, sheet metal, etc. Mass production is the only way to make the die casting viable.

 

5.  Risk of porosity 

Since the molten metal, which has no gas permeability, is injected into the die cavity at a high rate of speed, die casting has the risk of creating a gas cavity on the product being cast. Therefore, the die-cast components are not suitable for high working temperatures.

 

Conclusion

Die casting is superior to other manufacturing techniques because of its modern, unique advantages and environment-friendly nature despite its minor drawbacks. Currently, automation in die-casting is at its height and applies to almost all Industries sectors, from renewable energy and defense to healthcare, aviation, and automobiles. Our firm ProleanHub provides professional Aluminum die casting services from experienced professionals. Our expert designers, who have many years of industry experience, create the molds for your product, and we use computer simulation to ensure the quality of die-casting products. In addition, our quality control engineers monitor each casting process step to maintain the standard and tolerance. So, if you need any die-casting-related services, do not hesitate to contact us.

 

 

FAQ’s

 

What distinguishes hot from cold chamber die casting?

The shot chamber in a hot chamber die-casting process is heated before molten metal is injected into it. Another difference is that the cold chamber method is used for metals with high boiling points while the hot chamber method is used for metals with low boiling points.

 

What is the main advantage of die casting?

 Die casting allows for creating complex geometries (such as engine blocks) with a high degree of dimensional accuracy.

 

Is the die casting an expensive process?

 

Yes, for the small-batch production. But for mass production, It is a cost-effective approach because a single die is used repeatedly to cast identical items.

 

In which industry is Die-casting used?

 

Die casting is mainly used to cast the automotive, Energy, Military, Medical, aerospace, and agriculture components.


Post time: Jun-23-2022

Ready To Quote?

All information and uploads are secure and confidential.

Contact Us