From engine blocks and cylinder heads to bicycle frames and garden furniture, the die-casting process has been used in producing a wide variety of products.
Die-casting is one of the most creative and versatile processes for metal casting. In this process, a mold cavity is used to shape the object, and high pressure is applied to the molten metal filling the cavity. The raw material will be heated then and forced into the mold cavity. Once the molten metal has cooled off and hardened, a newly created casting is produced.
With its unique features, die-casted parts can be accurately accomplished. While die-casting is considered a highly versatile casting process, it has its own advantages and disadvantages, which we are going to explore here. At the same time, we will compare it to other manufacturing methods.
The Advantages of Die-Casting
Most companies choose die-casting to process different parts and components due to its numerous advantages. Here are some of them:
It Supports Various Types of Metals and Alloys
With die-casting, you have a wide array of metals and alloys you can use. One of the most popular options for this casting process is zinc because of its extreme strength and ductility. At the same time, die-casting is also relatively inexpensive, making it perfect for large-scale manufacturing. Other types of metals and alloys that can be used for die-casting are lead, aluminum, tin, copper, and magnesium.
It Offers High Production Efficiency
This production method is easy to automate. Generally, hot-chamber die-casting machines are capable of die-casting parts and components 400 to 900 times per hour. On the other hand, cold-chamber die-casting machines can manufacture parts 50 to 90 times per hour.
Exceptional Dimensional Accuracy and Smooth Surfaces
Since die castings have extremely high dimensional accuracy and excellent surface finish, die castings can be used right away. This means that you can save a lot of machining costs and improve the use of alloy. Since die-casting uses pressurized molten metal, manufacturers do not need to worry about rigid or rough die-casting surfaces. In fact, this process produces extraordinary smoothness on the surfaces of castings. Since the molten metal is enforced into the mold cavity, it will entirely fill the empty space, making sure that you will have a smooth surface.
Extensive Mechanical Properties
In the die-casting process, the molten metal will cool off instantly and crystallize under high pressure. As a result, the layer of crystalline grains is fine and compact. The hardness and strength are both extremely high.
It Produces Complex Thin-Walled Parts
Complex parts with thin walls can be produced through die-casting. This is something that cannot be accomplished with metal mold castings and sand castings. Aluminum alloy die-casted parts have a minimum wall thickness of 0.5mm, while zinc alloy die-castings have a minimum wall thickness of 0.3mm.
It Has the Ability to Embed Other Materials
You can choose to include inserts or complex fasteners in your final die-casted component. As a result, you can save a lot of money on the processing and materials costs. Die-casting can help you improve the performance of parts and obtaining complex shapes. Most of all, the time spent on assembly work can be minimized.
Parts and Components Can Be Easily Mass-Produced
Die-casted parts with specific shapes can be obtained easily with less machining or no machining at all. One of the greatest benefits of die-casting is its capacity to reduce the need for finishing operations. Compared to other types of casting processes, die-casted parts are often finished with the use of a machine. Unfortunately, these secondary machining operations can be burdensome and time-consuming. Die-casting can minimize the need for such operations. In most cases, die castings can be shipped right away once the casting process is done.
Diverse Surface Textures
There is a variety of finishing techniques and surfaces you can use for your die-casted parts. In this process, you can obtain textured or smooth surfaces.
The Disadvantages of Die-Casting
Anything with advantages also has some disadvantages. Here are some of them in the die-casting process:
Die Castings Can Easily Generate Porosity
During the die-casting process, the melted metal can quickly fill the mold cavity at an extremely high speed. At the same time, the mold material does not have any gas permeability. Parts created through die-casting techniques can easily generate gas cavities. Because of this gas cavity, die castings cannot be used at high temperatures or enhanced by heat treatment.
Furthermore, the machining allowance of the components should not be extremely large so that the hardened layer will not be removed and the surface exposed.
Not Applicable for Small Batch Production
Generally, die-casting is only intended for large batch production because it is costly and complicated, and only large-scale production can absorb the costs to make it cost-effective. It is not a practical choice for small-scale production.
Specific Weight Requirements
The die-casting process has certain weight specifications that must be adhered to. For instance, a specific casting might require a minimum weight of an ounce to 15 pounds. Incidentally, if the casting weighs less or more, it could suffer from certain defects.
Low Die Life for High Melting Point
Some metals used for processing die casting parts have a high melting point. They also have extensive requirements in order to resist heat deformation. At the same time, the life of these molds is low. Presently, the materials being used for processing die castings are magnesium alloys, zinc alloys, aluminum alloys, etc. Furthermore, ferrous metals are seldom used in processing die castings.
Requires Huge Capital Investment
Compared to other casting processes, the dies, the casting machines, and other related equipment used for producing die castings are costly compared to other types of casting processes. Keep in mind that it will require a unique type of casting machine that is costly to acquire and maintain.
Although manufacturing companies can choose to use zinc as the casting material in order to save some money, die-casting as a whole is still an expensive casting process. As a result, in order to make die casting an economical option, it requires a large batch production.
The Unique Advantages of Die-Casting
Compared to the components generated from other manufacturing processes, die castings have distinct advantages.
Die-Casting vs. Sheet Metal
Die-casting is capable of creating more complicated shapes and its wall thickness can vary. However, die-casted parts can replace multiple sheet metal parts, thereby making the product structure simpler.
Die-Casting vs. Plastic Injection
Die-casted parts are also harder, more durable, and more dimensionally stable compared to plastic injection. Die casting is also more resistant to heat and is far more exceptional than plastics with regards to its cost and performance. Additionally, die castings are highly stronger under load and can entirely resist any weather, UV, and stress cracking.
Compared to creating plastic injection molded parts, the manufacturing process for generating die casting parts is much faster. Nevertheless, plastics are less expensive based on their unit volume. They are excellent electrical insulators, sensitive to temperature, and may have inherent color properties that can remove finishing.
Die-Casting vs. Sand-Casting
Die-casting involves fewer processes compared to sand-casting. Since die-castings have thinner walls, they can tightly maintain their dimensions. Molds are used in die casting parts, giving them higher production efficiency. It requires less labor cost, and the surface is smoother.
On the other hand, sand-casting parts are created from ferrous metals and most nonferrous alloys that are not appropriate for die-casting. Its tool cost is much lower while it has a larger maximum size. It is also more economical to produce a small amount of these parts.
Die-Casting vs. Machining
Die casting parts have lesser processing costs and are lighter weight compared to machining parts.
Due to its advantages and unique advantages, die-casted parts are now commonly used worldwide. These die-cast products play an important role in different devices such as cameras, mobile phones, and laptops. They are also very useful in the automotive industry.
Among the differently manufactured products, die-casting parts appear to be on top of the list since they are environment-friendly, modern, and innovative. At the same time, consumers highly approve of these products. Die-casting technology is now highly developed. It’s no surprise that die-casting parts will now be widely used.
We hope that this investigation of the advantages and disadvantages of die-casting has been very helpful to you. SEI Castings manufactures custom die-casting products. If you want to request a quote, we encourage you to contact us at (408) 374-1031. We will be glad to provide you with professional service to meet your mass-production needs.