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machined aluminum

Machined Aluminum vs. Cast Aluminum: Which Is Right For Your Project?

When it comes to machined aluminum vs. cast aluminum, the choice depends mainly on your project needs. Both have their unique benefits, depending on the application.

Machined aluminum is best for projects that require precision and a high tolerance for tight tolerances and intricate parts. Cast aluminum is more suitable for larger parts with less complexity and applications where strength and durability are essential requirements.

So which is suitable for your project? This blog post will discuss the differences between machined and cast aluminum and help you decide which is best for your needs!

What Is Machined Aluminum And Cast Aluminum?

cast aluminum 750 400
Cast Aluminum

Machined aluminum parts apply to several manufacturing industries and come from machining processes such as CNC machining (comprising CNC milling, grinding, and CNC turning). Though all three are good aluminum machining processes, CNC milling is the most common machining method because of the complexity it can achieve.

CNC aluminum has excellent properties, such as low density and high strength. As a result, these boost its level of applications. In addition, the CNC machine has a high ability to manufacture top-notch aluminum. Machined aluminum comes from different alloys, which include:

  • Aluminum 6061: The Aluminum 6061 is considered the most popular due to its strong mechanical abilities, high weldability, ability to withstand severe conditions, and super bendability.
  • Aluminum 7075: Although it is not as popular as aluminum 6061, the Aluminum 7075 has a very high resistance to fatigue and weariness. However, its disadvantage lies in its cost and unsuitability for welding projects.
  • Aluminum 2024: Aluminum 2024 is a common alloy in the aerospace and military industry. It has good mechanical properties, such as high tensile strength and strong resistance to wear and tear. However, its drawbacks include low weldability and an inability to withstand corrosion.

The other alloys suitable for CNC machining include aluminum 2014, aluminum 5052, and aluminum 6063.

On the other hand, cast aluminum is aluminum material subjected to casting procedures like die casting, sand casting, shell molds, plaster molds, etc. Cast aluminum involves liquefying a solid block of aluminum alloy and pouring it into already-made special molds with the intended design. Common aluminum alloys used for this process include;

  • A380 alloy is very light in weight and effective at extremely high temperatures. It is also very suitable for complex parts because of its high durability.
  • A383 aluminum alloy is a good conductor of heat and can withstand corrosion. However, the degree of such properties is lower than A380, especially in terms of durability.
  • A360 is highly ductile and can resist corrosion better than A380 and A383. It is also favorable for manufacturing complex parts. However, it is more difficult to cast than the first two mentioned earlier.

The Benefits Of Machined Aluminum

Machined aluminum has wide applications in several industries based on its properties. Below are a few advantages of using the types of aluminum in your project.

Complex Shapes and Precision

complex aluminum parts
Complex CNC Machining Aluminum Parts

Subjecting aluminum to CNC machining techniques, such as milling and turning, makes it easier to achieve parts with complex designs. This is because of the technique’s tight tolerances, precision, and accuracy. As a result, CNC-machined aluminum parts are suitable for making parts that require high accuracy and precision, e.g., automotive and aerospace parts. 

High corrosion-resistivity

When exposed to harsh conditions, machined aluminum parts forms a protective layer of aluminum oxide that helps prevent corrosion and protects it from oxidation. This protective layer is responsible for using parts made from this material in different environmental conditions. Aside from that, it reduces the cost of maintenance.

High strength and lightweight

Machined aluminum comes from aluminum, making them very lightweight. Aside from that, they have a high strength making them suitable for making parts with structural applications. For example, they are very popular in the aerospace industry because of these properties.

Good conductivity and Temperature resistance

It can conduct heat and electricity, increasing its usability in various applications. Furthermore, it has a high-temperature resistance which increases the flexibility of its application.


anodized aluminum colors
Anodized Aluminum Colors

CNC-machined aluminum parts have a high level of aesthetics. Parts subjected to the techniques have a machined finish. However, subjecting the parts to other finishing options is still possible.

The Benefits Of Cast Aluminum

Cast aluminum alloys have wide applications in several industries based on their properties. Below are a few advantages of using the types of aluminum in your project.


Unlike machined aluminum alloy being finished parts, cast aluminum is subjectable to machining. As a result, they are more versatile.


Cast aluminum is a cost-effective option, unlike CNC machined alloy, due to the lower investment cost.

Long lifespan

It can withstand rust well, which increases its longevity. With cast aluminum, you don’t need to worry about low durability. Furthermore, cast aluminum has high wear and tear resistance. As a result, there it incurs a lower maintenance cost. 

Environmentally friendly

Cast aluminum is recyclable as the waste material is subjectable to a casting process. As a result, they are an eco-friendlier option.

When to use machined aluminum vs. cast aluminum

Both machined aluminum and cast aluminum have excellent properties. However, they have different properties, benefits, and pros and cons, deciding their different applications. Below is a list of ways to determine when to use machined aluminum or cast aluminum;

Aluminum types and alloys

The alloys used in machined aluminum differ from those used in cast aluminum. Machined aluminum comes from aluminum 6061, aluminum 7075, and aluminum 2024, while cast aluminum especially uses A360, A380, and A383.


Cast aluminum is similar to the injection molding process in creating different shapes and designs. For example, cast aluminum is more applicable for producing a shell of street lights, while machined aluminum takes the shape of the layers with very small changes. Machined aluminum is suitable for producing the heat sink of a lamp and aluminum-featured doors or windows.

Conduction of heat

The thermal conductivity of cast aluminum made using die casting is about 90 w/m.k. On the contrary, machined aluminum is 180–190 w/m.k. This shows that the heat conduction is twice and machined aluminum is better suited for projects that require very high heat.

Cost and prices

Estimates of machined aluminum and cast aluminum can be made based on production volume, machine processes, labor, the price of the materials, and the tools to use. Generally, machined aluminum is more expensive than cast aluminum due to the machined used. However, proper calculations are important to determine the cost and price of both materials and their application. 

Level of output

Cast aluminum is suitable for high-volume production, while machined aluminum production is lower. For projects requiring the production of 1,000 parts or less per day, machined aluminum would be the right choice, while for projects that require the production of about 10,000 parts, cast aluminum is better.


Common applications of machined aluminum parts are in making components of products such as downlights, ceiling lamps, doors, and windows. On the other hand, cast aluminum is applicable in making parts used to produce automobiles, street lamps, and even mobile devices.


When deciding between machined aluminum vs. cast aluminum for your project, it is crucial to consider your needs and budget to ensure you make the better choice.

The experienced team of AT-Machining is ready to help you find the perfect aluminum solution that meets your needs. Contact us today to get started on your next project!

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Hey there, I’m Sam!

From AT-Machining, I’m a CNC Machining Expert in this field for more than 20 years.  We offer cost-effective machining services from China. Ask for a quote for your ongoing or upcoming projects now!

Best Regards, Sam, Co-Founder

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