Recognized for being incredibly lightweight and durable, aluminum is one of the most popular materials used in the production of functional parts and prototypes. It also offers impeccable corrosion resistance, thermal and electrical conductivity, and also retains dimensional stability even in high temperatures and harsh environments.

Since this particular metal has such a high melting point, the optimal way to cast aluminum parts is by utilizing the aluminum die casting process. This metal casting process forces molten metal into a mold cavity under high pressure. Aluminum die casting requires the use of a mold cavity, which is created using two hardened tool steel dies that are machined into a specific shape. With aluminum die casting, a cold-chamber machine is utilized.

Aluminum die casting reduces the amount of steps needed in production and prototyping, ultimately reducing manufacturing costs, while also providing parts with a high-quality surface finish and exceptional dimensional consistency. This technique is especially advantageous in small-to-medium sized castings, and is widely used in industries such as automotive, aerospace, medical and more.

However, in order to optimize the part quality in the aluminum die casting process, there are a few critical factors that you should keep in mind. With these tips, you can utilize Goal Sure’s professional-grade aluminum die casting services to its fullest potential, while also gaining a better understanding of this extremely popular manufacturing technique.

Understanding All Design Aspects and Geometric Features

Before a designer or engineer can utilize aluminum die casting to its full potential, it’s important that they first understand the design limitations and common geometric features that can be accomplished with this manufacturing technique. Here are some factors that you should keep in mind when designing a part for aluminum die casting.

• Draft – In aluminum die casting, the draft is considered as the amount of slope given to the cores or other parts of the die cavity, which makes it easier to eject the casting from the die. If your die cast is parallel to the opening direction of the die, the draft is a necessary addition to your casting design. If you optimize and implement a proper draft, it will be easier to remove the aluminum die casting from the die, increasing precision and resulting in higher quality surfaces.
  
• Fillet – The fillet is a curved juncture between two surfaces that can be added to your aluminum die casting to eliminate sharp edges and corners.
  
• Parting line – The parting line is the point where two different sides of your aluminum die casting mold comes together. The parting line location represents the side of the die that is used as the cover and which is used as the ejector.
  
• Bosses – When adding bosses to aluminum die casting, these will act as mounting points for parts that will need to be mounted later on. In order to optimize the integrity and strength of bosses, they should have the same wall thickness throughout the casting.
  
• Ribs – Adding ribs to your aluminum die casting will grant more support to designs that need maximum strength while still maintaining the same wall thickness.
  
• Holes – If you need to add holes or windows into your aluminum die casting mold, you’ll need to consider the fact that these features will grip to the die steel during the solidification process. To overcome this, designers should integrate generous drafts into hole and window features.
  

These are just the basics of what you should know when designing for aluminum die casting. If you want to optimize your mold further, you can contact Goal Sure’s expert manufacturing team for assistance.

Porosity

Porosity is the biggest problem in the die casting process. Die-casting processes are often used to make light parts from light metals to replace steel or iron parts. Since the inherent strength of light metals is lower than that of steel components, any situation that reduces the strength of components should be avoided. The small holes in the cross section of the casting will have a large effect on its tensile strength.

There are two main types of pores, one is stomata. Air holes are the result of the high-speed injection of molten metal into the mold. However, the presence of moisture in the mold or the decomposition of any organic compounds in the mold or cylinder will increase the porosity. Since all mold and punch lubricants may contain moisture, organics, or both, these substances can cause porosity problems. Dongrun Casting's well- designed products produce only a small amount of decomposition products, and all moisture is evaporated or blown dry before the molten metal is injected into the mold, thereby minimizing porosity.