Aluminum Die Casting Design Guide | Tips for Producing Better Parts

Every manufacturing process starts with a design, and the same goes for aluminum die casting. One way to ensure optimal production efficiency of aluminum die-casting is by perfecting the design phase of manufacturing. Due to this, we provide a guide to help both manufacturers get a better grasp of the aluminum casting design process.

If you want to learn more, please visit our website.

In this aluminum die casting design guide, you will get great insight into this die casting process, the importance of DFM to the process, and great tips for producing better aluminum casting parts. So, read on to get this great information.

Brief Overview of Aluminum Die Casting

Invented in , die casting has been one manufacturing process in the industry for a long time, with its ability to produce parts and products that have intricate parts and complex geometry with high precision. The aluminum die casting process involves using extreme pressure to force molten metal into a mold cavity. This process occurs under extreme pressure.

There are different materials used for die casting but aluminum remains the most common and the top choice. This is because die-casting aluminum offers more advantages than other metals.

Here are other benefits of using aluminum for die casting;

Easy to Work With

One major reason why engineers prefer using aluminum for die-casting parts and products is its ease of castability. With its superior castability, engineers can create a diverse range of products. Another factor that makes it easy to work with is its heat and corrosion resistance. This allows aluminum to withstand higher operating temperatures better than most materials.

Lightweight

Aluminum is one of the lightest metals. Although light, aluminum is still strong and durable, making it the best material for producing lighter components for different industries.

Different finish options

Different finishing options are available for aluminum die-casted parts, ranging from electroplating and anodizing, chrome plating, and polishing to powder coating. With these different finishing options, manufacturers can create products with a customized appearance.

Importance of DFM of Aluminum Die Casting

DFM, also known as design for manufacturing, is an engineering term that means production optimization. Furthermore, DFM aims to make die-casting aluminum both easy and cost-effective. Its main focus is on the manufacturing method and processes employed in manufacturing a product.

Conducting a DFM analysis before engaging in die-casting aluminum is important. Manufacturing companies like RapidDirect recognize this, which is why we offer customers free DFM analysis before the die casting process.

With DFM, some problems that could arise if they use a particular die-casting process for producing a product can be detected. Discovering problems at this stage is often less expensive and time-consuming than noticing them later, during, or after the production run.

Generally, applying DFM in die casting aluminum helps manufacturers and clients maintain good product quality while reducing production costs.

Aluminum Die Casting Design Guide – 12 Tips for Producing Better Aluminum Casting Parts

Here are some factors to consider when designing aluminum die casting products you want to make using die casting. Besides, these tips in this aluminum die casting design guide take into consideration DFM best practices;

1. Choosing Suitable Aluminum Alloys

There are different types of aluminum alloy, and the material choice plays a huge role in determining the product design. Here is the thing, each alloy has its properties. And obtaining maximum strength and integrity from your aluminum die-cast component depends on your ability to pick the right design for the right alloy.

Due to the different constituent elements, properties like weight, conductivity, fluidity, melting point, strength, and weight vary between aluminum alloys. This variation in properties implies that not all aluminum alloys are suitable for die casting.

The most common aluminum alloys used are the A380, A383, and A413. They are popular due to their strength at high temperatures, corrosion resistance, high electrical and thermal conductivity, and ability to retain dimensional stability regardless of shape complexity.

2. Wall Thickness

A uniformly thick wall improves casting integrity and quality. The reason is that it facilitates better metal flow and solidification. Furthermore, it is best to keep wall thickness uniform throughout the aluminum die-cast part. 

But if a variation in aluminum die casting, wall thickness is a necessary aspect of the design, then do not abruptly introduce the change in wall thickness. A gradual transition in the form of radii or filet is best, so your design does not end up having sharp edges, except at places where the wall and parting line meets.

Also, avoid designing walls that are too thick or thin. Designing a thick wall might increase your aluminum part’s stiffness, but it could reduce the quality of the aluminum cast part. This is because the cast part might end up cooling selectively, as thicker parts take a longer time to cool. Also, the world’s current preference is lightweight products, and a thicker wall would considerably increase the weight of your aluminum die cast part.

On the other hand, it is not advisable to make your design walls too thin, as it would make the wall prone to warping due to low stiffness. The recommended wall thickness for aluminum die-cast parts ranges from 0.787 in – 0. inch. However, the size is subject to change depending on the part’s structure, size, the material used, and application, as you could have aluminum die casting components with wall thickness as thin as 0.020 in.

3. Parting Line

A parting line appears where the moving half and fixed half of a die meet. These lines could complicate the design and production process if the designer places product features along them. So a designer should try as much as possible to visualize where these lines would be and avoid placing elements there, to prevent an increase in the cost of casting and tooling.

4. Draft Angles

This is one area of the aluminum die-cast you should look out for. Also called draft, it is the inclination, angle, or tapering given to the cores and surfaces of parts at a 90-degree angle to the die’s parting line.

Draft lines are important as they make ejecting the aluminum part after die-casting easier. Without a sufficient draft angle, there is a high chance of damaging the die or part during the ejection phase.

The draft angle depends on the type of aluminum alloy, the type and thickness of the wall, and the depth of the surface. However, a draft angle of 1 – 2 degrees is usually enough for the optimal release of the aluminum part without causing damage to the die-casting part.

5. Ejector Pins

When designing a part, it is important to keep the location of the ejection pins in mind, as they help push the casting from the die evenly. These pins become important due to the solidification and shrinkage the cast aluminum part goes through, which results in the part clamping into the die. It would be difficult to get the aluminum cast part out of the die without the ejector pins.

It also takes considerable pressure to eject the die. This means that placing these pins on a thin casting wall would be counterproductive since the pins would push right through it. Always place the ejector pins on sturdy design features like bosses and ribs.

Additionally, remember ejector pins always leave a footprint after ejecting a casting, so avoid placing the cosmetic surface of the casting in direct contact with ejector pins when designing.

6. Fillets and Radii

Although people use these terms interchangeably and refer to the rounded edges of the aluminum die-cast part, they do not mean the same thing. The radii refer to the rounded outer edge of the part, while the fillet refers to the inside rounded corners.

Fillets and radii facilitate smoother metal flow. They also help reduce the disturbance created within the die during the metal injection. Both features are extremely important to the design of any aluminum die-cast part as they help parts attain optimal structural integrity.

Besides, it is best to use fillers and radii where two surfaces intersect because this intersection would result in sharp corners without them. What’s more, when creating fillers that are perpendicular to parting lines, an adequate draft angle is necessary.

7. Undercuts

Formed using secondary machining or retractable slide cores, undercut add to the cost and complexity of the die, which is why it is best to avoid them when making designs. However, undercuts are unavoidable in some situations. In this case, it is best to keep the number of outside undercuts minimum, as they require side cores and would invariably increase the tooling cost.

Also, when designing undercuts, avoid placing them underneath bosses because they might end up blocking the successful ejection of the aluminum casting. Furthermore, ask your manufacturer to use T or V-shaped tools to cut the cast, as these tools easily reach difficult places.

8. Bosses

Bosses act as mounting points and stand-offs. They are important, but designing them improperly could make manufacturing difficult and increase the cost of production. Designing them right entails providing sufficient drafts and giving the bosses the large fillets to facilitate the proper flow of molten metal. Also, aim for Boss uniform wall thickness.

9. Ribs

This part of the aluminum die-cast design adds strength by increasing its stiffness. Designed with metal savers (hollow sections), some ribs facilitate the production of excellent castings. It is often better to use ribs than to increase a section’s thickness. The reason is that making a section thicker makes it more porous, thereby reducing its structural capacity.

On the other hand, it is not advisable to overuse ribs, as it can increase stress concentration around the rib’s edges.

10. Holes and Windows

Holes and windows are not difficult to design, but do this with care to ensure optimal manufacturability. Furthermore, designs like this have applications in electronics such as calculators and laptops with many holes placed closely together.

Besides, numerous holes and windows in a design could make ejecting the casting a tad difficult. The reason is the cast part clamps down on the die due to solidification and shrinkage. However, using a good amount of draft helps prevent this ejection difficulty. What’s more, try to use smaller windows in your design since larger ones do not allow molten metal to flow properly, thereby compromising the cast’s integrity.

11. Shrinkage

Shrinkage is common and unavoidable. Any molten metal alloy would pass through some form of shrinkage when it starts to cool and solidify. So a good designer must factor in shrinkage in the product design.

Although unavoidable, there are ways to reduce shrinkage in a design. The first method uses metal-saving cores and thinner sections because thicker sections are more prone to shrinkage.

Another method is by adding squeeze pins. These localized pins help reduce shrinkage porosity. Also, adding flat and vertical ribs to product walls could reduce its shrinking tendencies.

12. Assembly Options

The assembly options available depend on the complexity of die-casted parts. Also, you must select the right assembly technique before designing the die-cast parts. Some common assembly options available for aluminum die-cast parts include threading, fastening, welding, cored holes, injected metal assembly, etc.

Transform Your Aluminum Die Casting Design into Finished Products

An outstanding design is a must-have, but you would need the right manufacturer to transform your design into aluminum die-casted products. RapidDirect is one of the best manufacturers to help you achieve this goal.

RapidDirect is a leader in the manufacturing industry, with vast experience in aluminum die-casting services. No DFM analysis for your design yet? Not to worry, our team of manufacturing experts will provide free DFM analysis for you, facilitating design optimization while saving time and money.

Unsure what metal alloy or finish options would be ideal for your aluminum die-cast product? We provide you with an array of materials and finishing options to ensure the final product meets industry standards. So, start your project now and contact us today to get top-notch custom die casting service.

Conclusion

As with any production process, the design phase comes first when considering aluminum casting. With this aluminum die casting design guide, we believe you already have a clear understanding of important factors in producing aluminum parts. Hope this will help you produce a better product.

If you are looking for a trusted and reputable company to handle the transformation of your aluminum casting design into a better product, RapidDirect is the best die-cast manufacturing company to help you achieve your goal. Besides, we offer you a free quotation and DFM analysis.

The unique thing about the die casting process is its ability to produce a wide range of parts with an extremely high degree of accuracy, quality, uniformity and surface finish.

The method is efficient to avoid the need for post-production machining and minimise fabrication time. Just imagine the amount of cost that can be saved by using these two methods.

The moulds used for die casting are made out of hardened steel which is good enough to handle various materials. The process of die casting is effective for materials with low melting points.

As per the reports, the market size for die casting has achieved an annual growth rate of 10.1%. The global aluminium dies casting size is about USD 24.91 billion.

The numbers indicate the increasing reliance on die casting for various metal alloys and their properties. The source of metals used for die casting will impact the overall finish and quality of the production.

In this article, we will discuss various alloys used in the die casting process. The die casting process’ result will be entirely dependent on the properties of metals such as melting point, conductivity, density, malleability, etc.

Different types of die casting alloys

Die casting alloys are mainly chosen depending on the purpose at hand. The most popular choices are magnesium, aluminum and zinc.

Other options can also be used, such as lead, tin copper and brass. 

However, these metals are less commonly used and are often treated as special materials for die casting. 

If you want to learn more, please visit our website Yuhui.

Since different alloys have different properties, the manufacturer needs to understand specific requirements and choose the best for the project.

Different types of die casting alloys 

Let us take a closer look at some of the different types of die casting alloys and their uses.

Zinc Alloys

One of the main reasons zinc alloys are used is that it is easier to cast and responds very well to the moulding process.

Zinc alloys are composed of multiple metals in specific ratios. Say, for example, a typical workpiece for zinc-based die casting consists of 7 to 10% tin, 4 to 7% copper, and 86% zinc.

The melting points of zinc alloys are in the range of 700 to 800 degree Fahrenheit.

A higher proportion of tin helps make the workpiece more flexible, while more concentration of copper helps to improve the rigidity.

Benefits and uses of zinc die casting alloys.

Zinc die castings are a suitable replacement for brass or cast iron but the tensile strength is much lower when compared to the other two metals.

The material cannot be corroded by the influence of seawater or alkaline substances. These are, therefore, used to coat the surface of metals to preserve the lustre.

Zinc based materials can withstand a force up to 17,000 pounds per square inch, but not beyond that.

As a result of this, the material cannot be used for any applications that involve enduring extreme amounts of force.

The mechanical property of zinc exceeds magnesium, bronze, aluminum, most cast irons and plastics.                                    

Brass and Bronze Alloys

These materials are commonly used to create camshaft components, decorative products and washers.

Brass alloys consist of 40% zinc,60% copper and 2% aluminum. However, there are several variations, as well.

Benefits and uses of Brass and Bronze die casting alloys

Die casting brass and bronze alloys yield products with extremely accurate interior specifications and with a durable surface.

Brass and bronze materials can be effectively used for die casting, just like zinc-based alloys.

Holes can be drilled into the brass alloys only after casting but not during the casting process.

The brass alloys are highly suitable for applications that require a high tensile strength of up to pounds/square inch.

Brass and bronze alloys can be used for products with thickness 1/32 of an inch and weighing up to fifteen pounds.

Aluminum Alloys

Since these are generally lighter and stronger when compared to most zinc-based alloys, aluminum alloys are slightly difficult and expensive to create when it comes to die casting. 

Aluminum die casting is extensively used in automobile gears and parts. Previously it was also used to create surgical instruments.

Benefits and uses of Aluminum Die Casting alloys.

The material has a high melting point of degree Fahrenheit and is most commonly composed of 92 percent aluminium mixed with 8 percent copper. 

Adding magnesium helps boost the tensile strength from 21,000 pounds /square inch to approximately 32,000 pounds/square inch.

On the other hand, adding nickel helps to provide a better surface finish and improve rigidity.

Tin Alloys

Tin Alloys are used in applications that require corrosion resistance. These are the most commonly and widely used in the food industry. 

The percentage of metals in the tin alloys can vary greatly depending on the purpose at hand. 

Benefits and uses of Tin alloys

Tin alloys are highly valued for their resistance to acids, water and alkaline, making them an excellent choice for coating the inner walls of cans for storing beverages.

In general, tin alloys consist of 4 percent copper, 6 percent antimony and 90% tin. Die castings made out of tin alloys have a thickness of 1/32 of an inch and weigh under ten pounds.

The tensile strength is relatively low, below pounds/square inch.

What is the best type of metal for vehicle parts? 

Moving vehicle parts will be under a lot of stress, and alloys should be handpicked to ensure that the components remain effective and efficient throughout the year.

Aluminum parts are excellent, but they will be expensive. Usually, aluminum-zinc alloys are preferred automotive die casting moving components such as gears, clutch wheels etc.

The high durability and corrosion resistance make it a popular choice for truck, car and other vehicle parts.

The excellent stiffness- weight ratio minimises the weight to the maximum possible extent and improves the mileage for heavyweight carriers.

The high thermal and electrical conductivity adds to its advantages, making it an excellent choice for computing, lighting, and electronics.

What is the best type of metal for making ammunition?

Since guns and ammunition have to smoothly operate at a high temperature, the metal chosen should be highly resistant to corrosion and temperature.

The most popular choice of metal while making guns are aluminum or zinc alloys. Aluminum is used in places where high strength is not required, like trigger guards.

What is the best type of metal for Surgical Equipment?

Medical equipment greatly varies in its functionality, and the type of alloys used will depend on the purpose of the equipment.

In general, you could see the usage of magnesium, zinc or aluminum to make the parts.

Magnesium is an excellent choice for diecasts with excellent corrosion resistance, low density, high strength to weight ratio, good electrical and thermal conductivity.

Magnesium alloys help to create parts that are incredibly lightweight and long-lasting.

The downside of die casting the magnesium alloy is that it requires specialised handling requirements that several die casting industries may be lacking, earning it the name “specialty” alloy.

You need to find the proper manufacturer to produce high volume parts as there are constraints in manufacturer and availability.

Zinc die casts help manufacture surgical equipment that is extremely lightweight, improving the precision during the surgery.

Zinc die casts are used for patient-facing devices. As zinc provides a suitable surface for painting or metal plating, it can be attractively painted or coated to have a glowing lustre.

As the metal has a low melting point, the mold life is better than aluminum die casting but cannot be used for high-temperature applications.

How to choose a suitable alloy for your needs?

There are no hard and fast rules when choosing a metal alloy. It depends on the requirements and applications. Make sure that the metal that predominates in your die cast part is suitable for your product.

If your priority is that the diecast should withstand high temperature, it is better to go for an aluminum-based alloy. 

Do keep in mind that it requires a cold chamber die casting process for its manufacturing, while other alloys such as Magnesium or zinc work well with hot chamber die casting machines.

If your goal is to manufacture a lightweight part, it is better to choose Magnesium that is exceptionally light in weight. However, it is essential to understand that the metal is available only in limited supply.

Stainless steel and nickel alloys can be used if your main goal is to have corrosion resistance.

Brass alloys are the best for creating equipment and materials that have high thermal and electric conductivity.

Zinc alloys are the best for casting alloys with hardness, great strength and dimensional stability. Zinc allies give a natural glow after casting.

Bottom Line

While choosing a suitable metal for the precision die casting process, you will have to consider a variety of factors such as applications, the temperature at which it operates, availability of materials etc.

Thus an in-depth analysis of the requirement is necessary to zero in on the metal that works best for your required parts.

This article has discussed several metal alloys and their properties for the die casting process. The best way is to directly ask your die casting manufacturer about the choice of metals to handle your project. They might be able to help you to select the right option.

Are you interested in learning more about Automotive Die Casting Solution? Contact us today to secure an expert consultation!