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Why Use Aluminum Castings Rather Than Aluminum Billet?
The debate between billet and cast aluminum has been raging for years. People consider billet aluminum superior due to its machinability and strength. In contrast, they believe cast aluminum is more affordable and easier to work with metal. But which one is better? This article will explore the differences between billet and cast aluminum and why cast aluminum wins every time.
What is Billet Aluminum?
Billet aluminum is a type of metal created by taking a solid block of aluminum and then machining it into a desired shape. This process is called “forging” and is often done with a CNC (Computer Numerical Control) machine. The result is a part that is incredibly strong and machinable, making it ideal for applications such as pistons, connecting rods, and other high-performance components.
Billet aluminum is more expensive than cast aluminum due to the complexity of the forging process. It also requires a higher degree of skill to work with and is best left to experienced machinists. Despite this, billet aluminum is still widely used in the automotive and aerospace industries due to its superior strength and machinability.
What is Cast Aluminum?
Cast aluminum is a type of metal created by melting it down and pouring it into a mold. This process is called “casting” and is often done with a die-casting machine. The result is a less strong and machinable part than billet aluminum. Still, it is much easier and cheaper to work with.
Cast aluminum is often used in engine blocks, gearboxes, and other parts requiring less precision. It is also widely used in the automotive and aerospace industries due to its affordability and ease of use.
Aluminum sand castings can weigh a fraction of billet aluminum molds, thus allowing easier handling for Castek’s customers.
Benefits of Cast Aluminum
When compared to billet aluminum, cast aluminum has several advantages:
- It is much cheaper to produce, making it an ideal choice for those on a tight budget.
- It is much easier to work with, meaning novice machinists can still create quality parts.
- It has a much lower melting point, making it ideal for high-temperature applications.
- We can quickly and easily source it because it is much more widely available.
Strength Comparison: Billet vs. Cast Aluminum
When it comes to strength, billet aluminum is the clear winner. Due to the forging process, billet aluminum is much stronger than cast aluminum. It can withstand higher levels of stress and strain. This makes it ideal for parts that must be particularly strong, such as pistons and connecting rods.
Cast aluminum, on the other hand, is still strong but less strong than billet aluminum. This makes it ideal for parts requiring less strength, such as engine blocks and gearboxes.
Cost Comparison: Billet vs. Cast Aluminum
In terms of cost, cast aluminum is the clear winner. As mentioned earlier, cast aluminum is much cheaper to produce due to its simpler process. This makes it ideal for those on a tight budget, as it can be sourced quickly and easily without breaking the bank.
Billet aluminum, on the other hand, is much more expensive due to the complexity of the forging process. This makes it ideal for those willing to pay a premium for higher-quality parts.
Castings can be a much more economical option for larger molds and molds that have a deep draw (tall Z part height).
Aluminum billet molds used in molding operations require gun drilling for temperature control. This gun drilling operation can add significant costs and labor to the mold. When using aluminum castings, there is no need for gun drilling. The stainless-steel tubing is cast onto the aluminum castings’ back side to provide processing control.
There are significant savings on CNC machining hours when using aluminum castings. Castek “overcasts” the mold face, allowing them to immediately begin finish CNC programs instead of needing heavy roughing passes on billet aluminum molds.
Aluminum castings can save a great deal of project timing. On larger molds, the billet aluminum producers often have longer lead times or may be unable to produce a billet of that particular size. Castek has several large foundry flasks to hold the sand molds around your project and can custom manufacture a foundry flask to allow molding for these larger projects. This, coupled with reduced CNC machining hours when using sand castings, can reduce many weeks of overall program timing for your project.
Machining Comparison: Billet vs. Cast Aluminum
When it comes to machinability, billet aluminum is again the clear winner. You can work billet aluminum into intricate shapes and designs because of its superior strength, making it much easier to machine. This makes it ideal for those who need highly detailed parts, such as racing pistons.
On the other hand, cast aluminum is more challenging to machine and is best left to experienced machinists. This makes it ideal for those who need simpler parts, such as engine blocks and gearboxes.
Finishing Comparison: Billet vs. Cast Aluminum
When it comes to finishing, both billet and cast aluminum have their advantages. Billet aluminum is much easier to polish and can be worked into a mirror-like finish, making it ideal for those who want a particularly shiny part.
On the other hand, cast aluminum is much easier to anodize and can be dyed into different colors, making it ideal for those who need a part with a unique look.
Applications for Billet and Cast Aluminum
Billet aluminum is ideal for high-performance parts, such as pistons and connecting rods, as it is much stronger and easier to machine. On the other hand, cast aluminum is ideal for those who need simpler parts, such as engine blocks and gearboxes, as it is much cheaper and easier to work with.
Cast Aluminum Wins Every Time
The answer is clear: cast aluminum wins every time. It is much cheaper, easier to work with, and more widely available than billet aluminum, making it the ideal choice for most applications.
At Castek, we specialize in producing high-quality cast aluminum parts. Our team of experienced engineers and machinists in Pennsylvania and Ohio can help you create a part that meets your exact specifications. Please send us your part data or project outline, and a knowledgeable Castek team member will reach out right away to quote and help with your project!
