Chapter 1 Introduction

Die casting is a manufacturing process to produce parts from various metal alloys with high precision. The process involves the injection of molten metal under high pressure into a steel mold. When we use aluminum alloys as raw material, we call this process aluminum die casting. It is one of the most popular manufacturing processes for large volume production of metal parts.

In this Aluminum Die Casting Handbook, we have highlighted all the essential information about the aluminum die casting process. If you are new to aluminum die casting, we believe this handbook is all you need to get started.

History

Despite the massive popularity nowadays, it hasn’t been that long since aluminum die casting started being used in the industries. Compared to other metalworking methods that have been used in human civilization for centuries such as forging and investment casting, aluminum die casting is rather new to us.

The first die casting equipment was invented in 1838. Though, it was primarily used by the printing industry at that time for making movable type. However, the first die casting-based patent was approved in 1849. But the machines were still at an early stage and were hand-operated.

Over time engineers have developed a better version of the machine and it was slowly being adopted in other industries as well. In the late 1950s and 1960s, General Motors developed a process called Acurad to cast low-iron aluminum alloys. This process was closest to our modern-day aluminum die casting process. Since then, the process was continuously upgraded to increase its efficiency and capacity.

Impact on the Industry

The aluminum die casting process had completely revolutionized the manufacturing industry. Initially, lead and tin were mainly used in the die casting process. But, by the 1930s, most low melting point metal alloys such as Aluminum, Zinc, Magnesium could be successfully die casting.

The discovery of Aluminum is rather recent. Even a few centuries ago, aluminum used to be a very rare metal. It was even costlier than gold at some point. However, by the 20^th century, proper Aluminum refining processes were put into practice, which made mass production of Aluminum possible.

It soon became one of the cheapest yet most efficient metals in terms of strength-to-weight ratio. Therefore, aluminum die casting, in particular, gained massive popularity among manufacturers. It has replaced many commonly used alloys and manufacturing techniques of that time. Today, a significant market share of the global manufacturing industry belongs to aluminum die casting alone.

Chapter 2: Aluminum Die Casting Process

The complete process of aluminum die casting consists of some fundamental steps. But, before you can get started with the process, you have to prepare a set of molds called die based on the product to be manufactured. This process is called die tooling. You only have to prepare the molds once, and you can use them to cast thousands of parts.

Basic Steps of Aluminum Die Casting

We have explained the basic steps involved in a typical aluminum die casting process below.

Melting

The first step is to melt the aluminum alloy inside a suitable furnace. Due to the aluminum alloy’s high melting point, the furnace is located outside the machine. The typical melting temperature of alloys is about  660^oC. However, for die casting, alloys must be heated to a higher temperature than the melting temperature to be able to pour it properly. For aluminum alloys, the pouring temperature range is 700^oC to 750^oC.

But caution should be taken not to raise the temperature higher than that, as it would adversely affect the quality of the casting. Also, note that a sufficient quantity of aluminum alloy is melted inside the furnace at once. For the rest of the session, we only carry the molten aluminum from the furnace and pour it into the injection unit.

Die Preparation

Before each casting cycle, the die halves are cleaned to remove any residue that may be left from the previous injection. Then, lubricant is sprayed onto the die halves to enable easier removal of the next casting. While lubricant is essential, it may not be necessary to spray it after every casting cycle.

Usually, lubricating the dies every 2 or 3 cycles is enough, though it can vary depending on some factors such as casting size and material. Once done, the dies are clamped together with a specified amount of clamping force to form a cavity. The clamping force is a key determinant of a die casting machine’s capacity. Bigger castings require machines with higher clamping force.

Pouring

Pouring of the metal sounds like a simple thing to do. However, it is an important step for aluminum die casting. The melting furnace is located outside the die casting machine. So, we need to transfer the molten aluminum to the shot chamber with the help of a ladle.

The pouring process is usually done manually by workers. However, there are robot-operated die casting machines as well. Automation of the process saves time and also eliminates the risk of hazards to workers.

Injection

Then molten aluminum is poured into the shot chamber, and injected into the die cavity using a plunger. The plunger gradually forces the molten aluminum inside to fills up the cavity. The plunger is powered by a hydraulic cylinder, and injection speed & force is specified based on the casting requirements.

Solidification

When the hot molten aluminum has taken shape inside the cavity, it is left inside the die cavity for a brief moment to let it cool down and solidify. During this time the plunger retains the applied pressure. When solidification is complete, the plunger retracts backward.

Ejection

Finally, the dies are opened to retrieve the casting. Usually, the moving die is equipped with an ejection mechanism that automatically pushes out the completed casting from the die using ejector pins. Or, it may also be manually removed from the die.

Different Aluminum Die Casting Processes

The aforementioned steps are the most widely used process for aluminum die casting. However, there are various methods for aluminum die casting. The processes are differentiated from each other based on various criteria. The most common processes are,

• Pressure Die Casting
• Vacuum Die Casting
• Gravity Die Casting
• Squeeze Die Casting
• Semi-Solid Die Casting

We have discussed each of the processes in brief to give you some basic ideas.

Pressure Die Casting

Pressure die casting is one of the most common forms of aluminum die casting that is widely used in the industry. In this process, external pressure is applied to cast the parts. Based on the extent of pressure applied during the process, aluminum pressure die casting can be further classified into the following two categories:

1. High-Pressure Aluminum Die Casting
2. Low-Pressure Aluminum Die Casting

The basic steps of aluminum die casting discussed previously mainly resemble the high-pressure die casting process. It is by far the most popular aluminum die casting methods that are used by more than 70% of the manufacturers. It is a rapid process that and mainly suitable for the mass production of parts.

On the contrary, low-pressure aluminum die casting is preferable when we are dealing with larger parts and want to reduce the porosity in casting. However, the process is rather slow, and it is difficult to cast intricate parts with thin walls.

To learn more, you can read our detailed blog on Pressure Die Casting or another blog that shows the comparison of High Pressure vs Aluminum Die Casting.

Vacuum Die Casting

The vacuum die casting process aims to reduce or nearly eliminate pores in aluminum die casting parts. The machine setup and process are almost the same as that of a typical high pressure aluminum die casting process. Therefore, it can be thought of as an upgrade to the conventional process.

Here, an additional vacuum unit is attached to the die cavity to remove the entrapped air prior to every casting cycle. So, it is also known as vacuum-assisted die casting.

Read our dedicated blog on Vacuum Die Casting or our FAQ Guide if you wish to learn more about this process.

Gravity Die Casting

The gravity die casting process is one of the most simple and inexpensive aluminum die casting processes. Unlike the other die casting methods, gravity die casting does not require any external pressure. Molten aluminum is gradually poured into the mold cavity to fill it up.

The finished product has low porosity and a good surface finish. However, this process is considerably slow as it takes place under the gravity force. Therefore, it is mainly used for low volume casting requirements or prototyping of parts.

Here’s a link to our separate blog on Gravity Die Casting.

Squeeze Die Casting

Squeeze die casting is an upgrade to the traditional gravity die casting process. The initial steps are the same as that of gravity die casting. After filling the cavity, slowly pressure is applied to the casting to make it more compact and pore-free. This process is more costly but ensures higher quality for the casting.

Check out our Squeeze Die Casting blog to learn about the complete process. It will also help you understand whether this process is suitable for your project.

Semi-Solid Die Casting

As the name implies, semi-solid die casting deals with aluminum alloys in a semi-solid condition instead of fully melting them. The main goal is to retain the mechanical properties of a forged part, yet do it more conveniently. There are currently three methods to work with semi-solid alloys,

1. Rheocasting
2. Thixocasting
3. Thixomolding

Aluminum semi-solid die casting is done using the rheocasting or thixocasting process. We have a separate blog discussing the Rheocasting and Thixocasting Differences.

You can check out our Semi-Solid Die Casting blog as well. It will help you understand the difference between the conventional and semi-solid die casting processes.

Chapter 3: Aluminum Alloy Materials

Aluminum die casting is done with some specific type of aluminum alloy. This section will discuss the basic characteristics of aluminum alloys in general, and also the properties of common aluminum alloys used for die casting.

Characteristics of Aluminum Alloys

Aluminum alloys have some unique properties that make them an excellent choice as die casting material. Below we have discussed the main characteristics of aluminum die casting alloys.

• Lightweight; has a superior strength-to-weight ratio
• Excellent corrosion resistance
• Components can operate under high temperatures
• Excellent Tensile strength and hardness
• Excellent thermal and electrical conductivity
• Can be fully recycled
• Parts have a good surface finish
• Great EMI and RFI shielding Properties

Types of Alloys

There are numerous types of aluminum alloys in existence. But, only a selected few of them are used die casting, including,

• A304 (K-Alloy)
• A360
• A380
• A383 (ADC12)
• A413
• B390

Each of these alloys has slightly different characteristics compared to the properties of raw aluminum. We have briefly discussed each of the alloys used for die casting.

A304 (K-Alloy)

It is a patented aluminum alloy that was specially designed to protect parts from hast conditions. The A304, also popularly known as K-alloy has superior corrosion resistance along with better thermal conductivity which offers improved cooling of parts.

Moreover, K-alloy diecast parts have excellent surface finishing which eliminates the need for basic surface treatment operations like painting or anodizing. You can read our detailed blog on K-alloy Properties And Advantages and Industries using K-alloy to learn more.

A360

A360 aluminum alloy ensures better pressure tightness and fluidity for diecast parts. Due to having a higher silicon content, the A360 exhibits better corrosion resistance even in a higher range of temperatures.

A380

A380 is one of the most popular alloys in the aluminum die casting industry. It can be thought of as an all-rounder alloy with a great combination of mechanical, thermal, and casting properties. It is convenient to work with and has a perfect balance of strength and performance which should be ideal for most applications.

Read our dedicated blog on Aluminum A380 Alloy to learn more.

A383 (ADC12)

A383, also known as ADC12. It is often used as an alternative to the A380 alloy as their properties are quite similar. But it has better fluidity, therefore is easier to work with. It provides good dimensional stability and can cast parts with intricate details.

A413

The A413 has a good balance of physical and mechanical properties. It has good pressure tightness and is not prone to hot cracking. Therefore, it is an ideal choice for die casting parts like hydraulic cylinders. Moreover, its fluidity allows the casting of complex shapes as well.

B390

B390 aluminum alloy is the right choice if you are need parts with more hardness and wear resistance. It is commonly used in the automotive industry for casting parts such as pistons for the combustion engine and cylinder bodies for brakes and compressors.

Composition of Alloys

Different aluminum alloys have different compositions of alloying elements in them. A comparative chart of the ratio of alloying elements present in each type of aluminum alloy is shown below:

Table 1 – Composition of Aluminum Alloys

*Aluminum is the primary/base metal here. The total percentage varies depending on the percent of the alloying elements.

Properties of Alloys

The difference in alloying composition of the alloys affects their mechanical and physical properties. Below we have shown the comparison charts of the mechanical and physical properties.

Table 2 – Mechanical Properties of Aluminum Alloys

Table 3 – Physical Properties of Aluminum Alloys

Aluminum vs Other Die Casting Metals

There are various die casting metals in the market including aluminum. However, they are primarily non-ferrous metals and their alloys. Apart from Aluminum, some other non-ferrous metals used for die casting includes,

• Zinc
• Magnesium
• Copper
• Titanium
• Tin
• Lead

Aluminum die casting has the largest market share compared to other metals. However, there are certain applications when other metals could offer better value. Zinc is the second most die casting metal after aluminum.

Magnesium and Titanium are mainly popular in industries with a focus on lightweight metals. But Tin and Lead are rarely used nowadays due to their hazardous impacts.

Below we have shown a comparison among various die casting metals.

Table 4 – Comparison Chart of Aluminum vs Other Die Casting Metal

*The values can vary for different alloys of the same metal.

Now, each of the aforementioned metals has different types of alloys as well. For example, Alloys of Zinc are Zamak and ZA alloys. However, some metal alloys don’t belong to a specific metal group as they consist of a significant percentage of two or more alloying elements. Example of such alloys includes,

• Brass, Alloy of Copper and Zinc
• Bronze, Alloy of Copper and Tin

However, Brass and Bronze is not your every diecast metal. They are difficult to cast as they have a high melting temperature due to the high percentage of copper. So, the manufacturing process is more complex and expensive. Therefore, their scope of application is limited to some specific industries.

Chapter 4: Aluminum Die Casting Equipment

Aluminum die casting is a sophisticated metalworking process involving the use of various types of equipment. A typical casting process requires,

• CNC machine for tooling of dies
• Furnace for melting the aluminum alloy ingots/billets
• Cold chamber die casting machine for casting the aluminum
• Additional equipment for post-processing and surface treatment of castings

However, we will only discuss the cold chamber machine that casts the aluminum here. You can check out our other blogs if you wish to learn about various other equipment involved in the complete process.

Components of Die Casting Machine

A typical cold chamber die casting machine can be divided into three units or compartments based on the processes taking place.

• Injection Unit
• Casting Unit
• Clamping Unit

Now, each of these units is comprised of several smaller components. The components of a conventional die casting machine and their function are briefly discussed in the following section.

Injection Unit

The main components of the injection unit of a cold chamber aluminum die casting machine are the shot chamber, plunger, hydraulic cylinder, shot sleeve, etc.

Shot Chamber: Molten aluminum transported from the furnace with a ladle is poured into the shot chamber.

Plunger: The plunger is a rod with a flat cylindrical head that pushes the molten aluminum through the shot sleeve into the die cavity. It is made up of higher quality material to reduce wear.

Hydraulic Cylinder: This is what powers the plunger. It regulates the pressure and speed at which the plunger pushes the material. The injection pressure applied can vary from 2000 psi to 20000 psi. The injection pressure is usually decided based on the volume of casting.

Shot Sleeve: It is the elongated section connecting the die cavity with the shot chamber.

Casting Unit

The casting unit is where the molten aluminum alloy takes shape of the desired product. All the necessary components are within two die halves, which include the Moving Die, Fixed Die, Core insert, Ejector Plate, Ejector Pins, etc.

Fixed Die: The fixed/Cover Die remains stationary during the casting process, therefore it is also known as the stationary die. It holds one part of die inserts.

Moving Die: It is also known as the ejector die. This part houses the ejection mechanism of the machine. During a casting process, only this die half moves perpendicular to the parting line.

Die Inserts: Some machines have a set of removable components called the core insert and cavity insert. Together they form a cavity and give the desired shape to the material. The die inserts are made by CNC machining and can be mounted into the main holding dies.

Ejector: The ejector comprises the ejector plate, pins, retaining plate, and a box that holds them together. The whole setup is mounted into the movable die. The ejector plate holds together a set of ejector pins. The ejector plate pushes the ejector pins forward to eject the casting out of the die.

Clamping Unit

The clamping unit contains all components required to power the die locking and opening mechanism. The capacity of the aluminum die casting machine is measured based on the clamping force. Larger castings require equipment with higher clamping force and vice versa.

The clamping unit has several powerful hydraulic pistons/clamps that move the moving die. The total clamping force dictates the maximum volume material that can be cast successfully. Typically, the clamping force of cold chamber aluminum die casting machines can range from 100 to 2000 Ton.

Types of Dies

Depending on the structure of a mold or die, it may be classified into the following types:

• Single Cavity Die
• Multi-Cavity Die
• Unit Die
• Combination Die

We have discussed each type of die type including their structure and application below.

Single Cavity Die

It is the simplest type of die consisting of only a single cavity. Therefore, it can only cast one type of part at a time. It is best suited when the production volume is low. However, some complex parts require special features in the die such as side cores. Intricate parts need to be cast separately in a single cavity die.

Multi-Cavity Die

The multi-cavity die will be your choice of die, when dealing with a large volume of a single type of part. The initial investment will be higher as more tooling operations will be required for the additional cavities. Moreover, multi-cavity casting will require more powerful die casting machines as well. However, the production cost will be subsided over time for large volume production.

Unit Die

Unit dies are also known die inserts. It is a preferable option when manufacturing high-mix, low-volume parts. It requires significantly less investment, as we only have to change the die insert instead of the whole die. Moreover, unit dies usually have a single cavity only, and they can be changed anytime to cast various types of parts.

Combination Die

A combination die is similar to a multi-cavity die. However, in this case, a single die is used to cast multiple types of parts. A combination die is usually used to cast a set of parts that belongs to a particular product assembly. It can substantially reduce the production time and cost.

Important Parameters and Specifications

Understanding the various specification of aluminum die casting machines are essential for not the manufacturers but also the customer/client as well. It will allow you correctly estimate the requirements for your die casting project and, also to assess the capability of a manufacturer. We have briefly discussed some of the important parameters/specifications below.

Die Locking/Clamping Force:  It is one of the key indicators of the capacity of aluminum die casting equipment. Equipment with higher clamping force can maintain better precision. The clamping force is usually a limiting factor for the maximum volume of casting producible.

Platen Size: It is the size of the die plates. It gives you some idea about the highest size of parts that can be cast using a die casting machine. Both the die height and width should be taken into consideration.

Die Thickness: The maximum and minimum die thickness is a limiting criterion for the thickness of parts.

Injection Force: It is the amount of pressure applied by the plunger during the injection phase of aluminum die casting. The die clamping force and injection force must be balanced properly to avoid defects such as the formation of a flash along the parting line.

Ejector Force: Once a casting cools down or solidifies, it tends to get stuck on the die. Ejector force is the highest amount of force applied by the ejectors to push out a solidified aluminum casting from the die.

Casting Size and Weight: Aluminum die casting machines are designed for the maximum size and weight of the casting. Previously, the maximum casting or shot weight was limited to around 10 kg. However, after the introduction of the Giga Press, the casting of even 80kg parts is now possible.

Popular Machine Brands

The aluminum die casting industry has undergone rapid growth over the last few decades. The involvement of modern technology has allowed manufacturers to significantly cut down on production costs while ensuring higher quality of parts.

Therefore, there is also competition among die casting equipment manufacturers to offer more advanced and efficient machines to us. Some of the top brands that manufacture and assembles die casting machines include,

• Idra
• Bühler
• Toshiba
• LK Machinery
• Frech
• Kurtz Ersa
• Yizumi, etc.

There are many other good brands as well, we only listed a few renowned ones here. Though, these are among the best in the industry. They have a very strong footprint in the manufacturing industry and are relied upon by industry experts.

Sunrise Metal is a leading aluminum die casting manufacturer in China. We invest in the latest technology die casting equipment from top brands like Toshiba, Bühler, LK Machinery, etc. This is part of the commitment to our clients to ensure the high quality and consistency of our manufactured parts. You can check out our complete lineup of die casting equipment available at our workshop as well.

Chapter 5: Advantages & Limitations

Aluminum die casting is one of the most reliable and efficient techniques for manufacturing metal parts. It has a great number of benefits with few limitations where it can be applied. We have briefly discussed its advantages and limitations in this chapter.

Advantages

Aluminum die casting offers a ton of advantages that makes it an ideal choice for most applications. Below we have discussed the advantages of aluminum die casting taking into consideration several factors.

Strength-to-Weight Ratio

Aluminum is well known for its lightweight compared to other metals. An average Aluminum alloy is almost three times lighter than Iron or Zinc. While Iron and zinc are stronger than aluminum, Aluminum has a superior strength-to-weight ratio. Making it an ideal choice for applications where weight is a big factor.

Versatility

One of the biggest advantages of die casting is its versatility. It allows casting of any shape or design very easily. Aluminum alloys have high fluidity and various other characteristics that make them the perfect material for die casting. So, aluminum die casting is widely used for the production of complex parts.

Surface Finishing

The manufactured parts have good surface finishing which minimizes the need for further post-processing. Also, it is possible to produce parts with both textured or smooth finishing. The castings have an aesthetic look and feel to them that reduces the need for costly surface finishing.

Durability

Aluminum castings have high corrosion and wear resistance compared to most other alloys. Aluminum alloy parts can be safely used in adverse environments. Moreover, there are numerous surface treatment options available as well that can further increase its durability.

Production Efficiency

Aluminum die casting offers superior production efficiency compared to other manufacturing processes. It has become the most popular manufacturing technology worldwide for the mass production of metal parts. And, all of this is achieved while maintaining high quality for the manufactured parts.

Production Cost

Aluminum die casting is considered one of the most cost-efficient production technologies for making metal parts. The lightweight, strength, durability, castability, surface finishing, and production speed all together make it a cost-effective alternative to other manufacturing technologies.

Limitations

Despite being one of the most versatile manufacturing technologies, aluminum die casting does have some limitations regarding its applicability. We have briefly discussed them below.

High Initial Investment

One of the main limitations of aluminum die casting is the relatively higher initial investment involved in the production. The dies required for casting are done by CNC machining, which can be quite costly and time-consuming depending on the complexity of the parts. However, once the mold is ready, it can be used for making thousands of parts, which eventually trims down the cost.

Not Suited for Low Volume

The high initial investment involved in the process also makes it less suitable for low volume production needs. However, some manufacturers utilize unit dies and rapid tooling technologies to make it more affordable for low to medium volume production.

You can check out Sunrise Metal’s aluminum die casting services, as we accept high-mix, low volume die casting projects as well.

Limited Casting Size

The size of parts we can manufacture by aluminum die casting is limited by equipment. The die size along with some other parameters such as the clamping force limits the highest volume of parts that we can cast. However, with the advancement of technology, size limitations are starting to become a thing of the past.

Recently, Tesla has started manufacturing using the Giga Press, the world’s largest die casting machine. It could potentially revolutionize the aluminum die casting industry by overcoming the existing limitations.

Chapter 6: Applications

Aluminum die casting is one of the most effective manufacturing processes for the mass production of high-quality metal parts. Therefore, aluminum diecast products have gained immense popularity among various industries lately. The demand for aluminum diecast parts is still on the rise as more industries are switching to aluminum die casting for high-quality parts at a reasonable price.

Let’s have a look at the applications of aluminum die casting in some industries.

Automotive Industry

The automotive industry has a huge demand for aluminum die cast parts at present. In order to increase the fuel efficiency of vehicles and make them more affordable, automobile manufacturers have taken a keen interest in aluminum die casting.

Modern aluminum die casting techniques have completely revolutionized the industry. Now, the manufacturing of complex automobile parts is easier than ever. You can read our FAQ guide on Automotive castings for more information.

Construction Industry

Megastructures such as bridges, high-rise buildings, and skyscrapers are becoming more and more common lately. However, the weight of construction material plays a big role in the design of structures, which eventually increases the construction cost.

Therefore, the utilization of aluminum castings in construction projects is increasing day by day. Also, construction equipment are making use of aluminum components as well.

Healthcare Industry

The healthcare industry has a large demand for high precision and complex parts. Aluminum die casting is used to produce housing and internal components for various medical devices such as dialysis equipment, ultrasound systems, hospital beds, monitoring devices, etc. Our Medical Casting blog can help you get more insight regarding the application of Aluminum castings in this industry.

Aerospace Industry

The aerospace industry has a particularly higher demand for parts with a good strength-to-weight ratio. The lighter the parts the better, as it can significantly reduce the fuel consumption. Aluminum and magnesium die casting has become more and more popular in the industry recently.

Energy Industry

The gas and oil sector utilizes various heavy machinery for drilling, piping, flow control operations. There is a good demand for die casting components in these machines. Moreover, the renewable energy sector has a large demand for die casting parts for making solar panels, wind turbines, etc.

Culinary Industry

The culinary industry has a huge demand for aluminum die casting products. They are vastly used for food processing. The lightweight, corrosion resistance, and excellent thermal conductivity of aluminum make it ideal for cookware and kitchen appliances.

Electronics Industry

The electronics industry has been showing increasing interest in aluminum diecast products recently. The lightweight and heat transfer properties have been the most intriguing thing for the electronics industry. The electronics industry utilizes aluminum die casting for making cover/enclosure and heat sink for various electronics products, such as smartphones, appliances, tv, computers, etc.

Marine Industry

The marine industry is utilizing aluminum die casting for making components and equipment for ships, submarines, and various marine installations. Some common applications include casting of pump housings, radar housing, display frame, pedal component, etc. You can check out our blog on Marine Casting to learn about the practical application of aluminum die casting in this industry.

Telecommunications Industry

Aluminum heat sinks, base plates, and enclosures are widely used in various telecommunication devices. The superior electrical & thermal conductivity, EMI & RFI shielding properties, and strength-to-weight ratio make them an ideal choice for telecommunication equipment. Read our Telecom Casting blog to learn about the potential applications of aluminum castings in this industry.

We only discussed some of the major industries utilizing aluminum die casting to give you some idea about the scope of its applications. Small or big, almost every industry has some demand for aluminum diecast components. Many are even inclining towards aluminum die casting to increase production efficiency and reduce production costs.

Chapter 7: Aluminum Die Casting Design

Design for aluminum die casting mainly refers to the model generated for tooling of the dies/molds. But, there are other factors to be considered as well. Because proper design practices are essential to achieve maximum efficiency in die casting. Therefore, the capability of a good aluminum die casting manufacturer also depends on their DFM practices.

In this chapter, we have briefly discussed various aspects of design for aluminum die casting.

Design for Manufacturing (DFM)

Design for Manufacturing (DFM) is the process to optimize a part design so that it is easy to manufacture. If manufacturing is made easier, it automatically reduces the production cost as well. Therefore, it is an essential step in aluminum die casting product design.

We have to take into consideration various factors when carrying out DFM for aluminum die casting. So, you should provide a clear idea about the possible scope of application of your product. Then we can select an ideal material, design, and process based on it.

Selection of Material

It is crucial to select the proper material for casting. We have already discussed the common types of aluminum alloys used for casting along with their material properties and characteristics. Choose a material that fits your product’s quality and strength requirements.

Geometric Considerations

There are various geometric features to consider when designing a part for aluminum die casting. They can greatly reduce the complexity in production as well as the post-processing operations. We have briefly discussed some of the key geometric considerations below.

Draft: Draft or draft angle is the tapering of design perpendicular to the parting line. It is the most important geometric consideration in aluminum die casting design. Keeping a minimum amount of draft is essential to allow easier removal of the casting without risking damaging it.

Fillet and Radii: Internal and external sharp edges in a design are replaced with a proper amount of fillet and radii.

Undercuts: Undercuts in design should be avoided or reduced as much as possible. They can make a die casting process very complex. If it is not possible to eliminate all undercuts, they should be strategically placed along the parting line.

Ribs: Ribs are used to reduce the thickness of a section. Properly designed ribs can significantly reduce the product weight, yet increase the stiffness and strength of a casting.

Parting Line: It is the line along which two die halves meet. Carefully planning the parting line orientation can substantially reduce the difficulty of the casting.

Wall Thickness: Wall thickness in casting should be designed as thin and uniform throughout the part. Too thick walls increase part weight and delays cooling. While making it too thin can cause warping during solidification and prone to failure due to lack of stiffness.

Holes and Windows: Closely spaced holes or windows in a design can cause various issues during casting. So, adequate precautions should be taken to avoid casting defects.

Bosses: Bosses can be thought of as mounting points for the assembly of parts. When adding bosses in design, adequate fillet along with ribs should be provided.

Design for Assembly (DFA)

Larger parts are often divided into multiple components for casting them easily. Therefore assembling them after casting is also an important part of the manufacturing process. The objective of DFA is to design the parts in such a manner that simplifies the assembly process. Reducing the number of parts is the most common approach in DFA.

Cost Optimization Tips

The quality of your aluminum die casting products will largely depend on your budget. While seeking higher quality is essential, the processes involved to achieve the desired quality should also be within your budget. You need not choose materials and processes that will yield parts that exceed your requirements.

Therefore, you should carry out a detailed cost estimation and take into consideration the possible output before going into production. Properly maintaining the aforementioned design aspects will also simplify the manufacturing process and reduce the overall production cost.

If you wish to learn more about the design of aluminum die casting parts, we recommend you to check out our Aluminum Die Casting Design Guide. There we have included detailed design guidelines for various geometric features along with necessary figures and charts.

Chapter 8: Aluminum Die Casting Defects

Aluminum die casting undoubtedly offers a wide range of benefits over most other manufacturing processes. Yet, the process can be subjected to various forms of defects. Therefore, minimizing the defects is the main challenge if you wish to enjoy the benefits it has to offer.

Below we have discussed the main types of defects that occur in aluminum die casting.

Gas Porosity Defects

It is one of the most common forms of die casting defect. Gas porosity is also referred to as air void or simply porosity. We can categorize porosity in die casting parts into different types depending on their form and location.

• Blisters
• Blowholes
• Open Holes
• Pinholes

Pouring Defects

It is the type of defect that is caused due to improper pouring of molten metal. The main reasons are usually insufficient molten metal or die temperature. Some common pouring defects are,

• Short Fill / Misruns
• Cold Shuts
• Scaling

Shrinkage Defects

Shrinkage porosity may occur during the solidification of casting. It can cause large voids inside the die casting part. Therefore, the structural integrity is weak and is prone to failure under heavy loading conditions. Shrinkage defects are mainly of two types:

• Open Shrinkage
• Closed Shrinkage

Shape Defects

Some factors can distort the shape of the casting or make it go out of alignment. We can categorize them as shape defects. Some common shape defect includes,

• Flash
• Shift
• Warping

Here, the shifting of two die halves causes flash to form along the parting line. Whereas warping results from differential solidification within a casting.

Metallurgical Defects

These types of defects mainly result due to an inconsistency in the chemical composition of a metal alloy. So, we can overcome such defects through modification of the chemical properties. Some common defects include,

• Hot Tear
• Hot / Hard Spots

Defects Due to Mold Design

A bad mold design or damaged mold can also contribute to the degradation of casting quality. Defects resulting from the mold includes,

• Run Out
• Swelling
• Cracks
• Scuffing

Apart from the aforementioned defects, many other types of minor defects can occur during the aluminum die casting process. You can read our detailed guide on various types of defects in die casting to learn more about them.

However, most die casting defects can be minimized or eliminated with the right manufacturing practices. You can check out our quality assurance technologies for aluminum die casting products to get some ideas.

Our advanced manufacturing techniques can nearly eliminate porosity and other common die casting defects. Moreover, We utilize the latest technology inspection devices to ensure top-notch quality and consistency for every casting.

Chapter 09: Aluminum Die Casting Products

We have previously discussed various industries that have a large demand for aluminum die casting. In this chapter, we have highlighted some common examples of aluminum die casting products to give you a clear idea of their scope of use.

EV Components: Electric-Vehicles (EV) are becoming increasingly popular due to their minimal impact on the environment. Manufacturers primarily use aluminum components for EV chassis construction to reduce the car’s weight, which increases energy efficiency. Some common aluminum diecast components used in EV includes,

• Engine cylinder head, block & gasket
• Transmission housing
• Gearbox & motor enclosure
• Heat sink
• Battery Cover
• Intake Tube
• Car Rims
• Chassis and other structural components, etc.

Aircraft Components: The lightweight of aluminum has made it an excellent material choice for manufacturing aircraft components. Most part of an aircraft including its fuselage is mainly made up of aluminum alloys. Diecast aluminum components are mainly used for structural and decorative components such as,

• Window frame
• Airline handrail
• Engine housing
• Brackets
• Control equipment enclosure
• Seat components, etc.

Marine Castings: Aluminum die casting products have superior corrosion and wear resistance. It is an essential property for any watercraft vehicle or ship as the marine environment is quite harsh on metals. Some common marine die casting products are given below:

• Radar housing
• Display frame & cover
• Camera lamp cover
• Heat sink
• Pump housing
• Display frame
• Engine enclosure
• Pedal component
• Seal rings and housing, etc.

Decorative Hardware: The versatility of the aluminum die casting process allows the manufacturing of parts with complex details. Therefore, it is used to cast decorative hardware such as,

• Gate and fence fittings
• Door handle
• Hydraulic door closer parts
• Wall hangers
• Brackets
• Door lock enclosure, etc.

Headlight Buckets: Aluminum die casting headlight frames are also known as buckets. They are commonly used in the headlight of various types of vehicles such as cars, bikes, and even locomotives. The aluminum base also serves as a medium for heat dissipation.

Industrial Parts: Aluminum die casting products have large demand in the industrial sector. Most modern industrial equipment comprises a good number of aluminum diecast components. Some common industrial parts include,

• Pump and motor housing
• Rotor and stator
• Impeller
• Gear valve
• Industrial fan housing
• Power tool housing
• Shaft Sleeve, etc.

Electro-mechanical Components: Electro-mechanical equipment has a greater focus on the thermal and electrical conductivity properties of metal parts. Therefore, aluminum diecast products are a great fit for this industry. Common electro-mechanical aluminum diecast parts are,

• Rotor and stator
• Cooling fan
• Motor shaft
• Heat sinks
• Equipment housing, etc.

Electronic Device Components: The lightweight and superior thermal characteristics have made aluminum diecast products a viable choice for electronic devices such as phones, computers, cameras, etc. Some common diecast products used in electronic devices are listed below:

• Electronic device Casing
• Heat sink
• Smartwatch outer bezel
• Internal frame
• Cooling fan, etc.

Medical Device Components: Medical equipment require a higher standard of production and inspection. The superior quality achievable by aluminum die casting products makes them an ideal choice for medical equipment. Some examples include,

• Surgical lamp base & bracket
• Patient bed gearbox housing
• Medical device structural parts
• Operation table gearbox
• Robot arm & base, etc.

Plumbing Fixtures: Zinc die casting is more common for plumbing fixtures. But, aluminum die casting products’ high resistance to wear and corrosion makes them suitable for plumbing applications as well. Common applications include pipe fitting, elbow, thermal valve, etc.

Home Appliance Parts: Diecast aluminum parts are used in numerous home appliances. The lightweight aluminum and extended durability make it a convenient choice for household appliances. To name a few,

• Ceiling fan cover
• Vacuum cleaner body
• Washing machine base, rotor
• Washing machine brake wheel pulley
• Speaker/Home theater casing
• The table fan base, etc.

Kitchen Appliances & Cookware: Aluminum die casting products are widely used for the manufacturing of various types of kitchen appliances. As a good conductor of heat, aluminum is also an excellent choice for cookware. Moreover, the high corrosion resistance makes aluminum diecast products a suitable choice for the kitchen environment. Some examples include,

• Cooking pots & pans
• Cookware lid
• Oven Interior & exterior
• Blender & grinder frame
• Gas stove & electric cooker frame, etc.

Panic & Fire Exit Hardware: Panic hardware used in emergency or fire exits used to be made with stainless steel. However, aluminum die casting has proven to be an excellent alternative to it. Some examples include,

• Panic bar chassis
• Push bar
• Exterior door lever
• Roller latch, etc.

Lighting Fixtures: Aluminum die casting is commonly used to produce decorative lighting fixtures. Moreover, aluminum diecast lamp bases are an essential component for modern led lamps as they serve the purpose of a heatsink as well. The thermal conductivity and heat dissipation characteristics of aluminum parts make them an ideal choice for lighting fixtures. Here are some examples,

• Decorative lighting fixtures
• LED street light housing
• Medical lamp mounting base
• Medical lamp bracket, etc.

HVAC Equipment Parts: Aluminum diecast products have many scopes of application in HVAC equipment. You will find diecast components in air compressors, condensers, and indoor units of air conditioning systems. They include,

• condenser cooling fan
• Scroll compressor spirals
• Compressor cylindrical head
• Vacuum pump heat radiating cover
• Compressor housing, etc.

Decorative Fence & Straighteners: Aluminum die casting provides a convenient means for making decorative fence spears for home or agricultural use. They can be installed on the gate, railing, and boundary wall. The process is widely used for large volume production of diecast aluminum fence caps, connectors, and straighteners.

Chapter 10: Aluminum Die Casting Services

The global aluminum die casting market share has rapidly increased over the last few decades. Due to the increasing demand for aluminum diecast components in various industries, more and more manufacturers are growing their interest in aluminum die casting.

While every manufacturer will promise to deliver top-notch quality, not all of them succeed in doing so. In this chapter, we have highlighted some key services that should be provided by a die casting manufacturer to help you choose the right supplier for your business.

Basic Die Casting Services

Apart from the casting process using a cold chamber die casting machine, a complete aluminum die casting production involves various other processes. They can include,

• DFM and PPAP Service
• Die Casting Tooling
• Die Casting Production
• Post-Processing by CNC Machining
• Surface Finishing, etc.

It would be best if you could find a manufacturer that provides all of the related services you would need for the production and processing of aluminum castings. Otherwise, dealing with multiple suppliers for casting, post-machining, and surface finishing would increase your production lead time coupled with various other issues during part handling.

Finding the Right Manufacturer for Your Business

We have shared some tips below that could help you look for a qualified aluminum die casting manufacturer.

• Check out the online business directories of aluminum suppliers, and compare their pricing and ratings with each other to evaluate them.
• The manufacturer should comply with international standards such as ISO 9001, IATF 16949, ISO 13485, etc. for aluminum die casting manufacturing.
• You may also seek recommendations from your business contacts who have experience with aluminum die casting suppliers.
• You can also visit international trade shows to get in touch with aluminum die casting suppliers from different parts of the world.

Outsourcing Diecast Components

Your options need not be limited within your country’s borders. In fact, you might even get a better deal from another country even with the shipping fees included. Moreover, if your country doesn’t have good aluminum die casting manufacturers, outsourcing them could be a viable solution.

If you wish to outsource your parts, then China could be a great option. China has the largest aluminum die casting industry in the world right now. Chinese manufacturers can offer higher quality parts at better pricing. And, it is possible due to having better technology, an abundance of natural and human resources in China.

Sunrise Metal is one of the leading aluminum die casting manufacturers in China. If you are looking for a reliable aluminum die casting manufacturer to outsource your parts, we invite you to have a look at our die casting services. We provide Rapid Prototyping, Die Casting Tooling, Die Casting, CNC Machining, and Surface Finishing services within our own facilities.

You can check out our capabilities as an aluminum die casting manufacturer to learn more about our services.

 Chapter 11: Future Development

Aluminum die casting is already a popular manufacturing process worldwide and is used by various industries. Yet, it continues to grow in popularity as new possibilities are added to this process with the advancement of technology.

In this chapter, we have discussed some of the emerging aluminum die casting technology that can leave a big impact on the manufacturing industry.

Giga Press

In the year 2019, aluminum die casting machine brand IDRA had launched the world’s first 6000T die casting machine and named it Giga Press. Shortly after that, LK Machinery introduced their IMPRESS-PLUS 6000T and 4000T die casting machines. In early 2021, LK introduced their DREAM PRESS series die casting machine with 9000T clamping capacity!

Tesla is one of the first companies to put this technology into action. They used the Giga Press to cast their latest Electric Vehicle, Model Y’s chassis. It has enabled them to cast more than 70 smaller components as a single homogeneous component. Thus, greatly reducing the time and cost involved in the part assembly.

Therefore, this technology has the potential to revolutionize the die casting industry as we know it. You can learn more about the Giga Press technology from our blog.

Predictive Analysis for Failure Detection

The current aluminum die casting production methods involve some manual procedures. But relentless research in this field has led to rapid advancement in the die casting industry and we hope to see more in the coming days. Digitization of die casting production is one of them.

One of the leading die casting equipment manufacturers, Bühler has been working on the digitization of the die casting process. They are using a machine learning algorithm for Predictive Analysis of die casting defects/failures. Moreover, they are running real-time performance tests by installing sensors inside the die casting cells.

CASTTRONICS Technology

The Fraunhofer IFAM has introduced the idea of digitation of aluminum diecast components. The idea is to install RFID transponders into a casting that can be used to permanently mark them. The parts can be uniquely identified by reading the data from the RFID anytime.

This will make die casting part identification and traceability a breeze for manufacturers. It can also be used for the measurement of parameters such as deformation, stress, and vibration in parts to get an early warning upon excessive loading. Moreover, it can be used to ensure the authenticity of parts and eliminate part plagiarism issues.

Chapter 12: Conclusion

We hope our aluminum die casting handbook was able to give you a proper understanding and insight into aluminum die casting. However, we only highlighted some of the important aspects of aluminum die casting here. But, it should be enough to give you a head start if you are new to aluminum die casting.

If you wish to learn more about the process, we have numerous blogs available on our site about aluminum die casting. We recommend you check them out. Also, you will find other blogs on our site about the latest manufacturing technologies.

Sunrise Metal is a professional aluminum die casting manufacturer. If you are interested in our services, you can contact our customer support team to discuss your aluminum die casting project. Also, you can get a get quote for your parts as well. We will respond to your inquiry within a day.