When it comes to material selection, it really comes down to your part’s function:

• What’s it going to do?
• What mechanical properties are you looking for?
• Will it be subjected to high stress or wear?
• Will your part include fine details (like lettering or your company logo)?

This table outlines the cast aluminum alloy designation system:

The second and third digits (xXX.x) are arbitrary numbers given to identify a specific alloy in the series. The number following the decimal point indicates whether the alloy is a casting (.0) or an ingot (.1 or .2). A capital letter prefix indicates a modification to a specific alloy.

COMMONLY USED ALLOYS IN OUR FACILITY

356.1 AND A356.2 GENERAL PURPOSE ALUMINUM

356.1 is a recycled material that’s popular amongst a wide variety of products because of its desirable characteristics. While this aluminum is known for its high strength, its counterpart A356.2 (original material direct from smelter) contains improved mechanical properties. A356.2 offers more strength, ductility and elongation.
The trade off is typically A356.2 is more expensive than 356.1.

413.1 HIGH FLUIDITY ALUMINUM

This recycled aluminum is commonly used on highly aesthetic and thin-walled castings.
This aluminum flows into castings very smoothly and is great to use if your part contains very  fine details (logos, letters, etc). In fact, 413.1 is so fluid, it has the potential to sneak into crevices it shouldn’t get into, so we control its fluidity by employing tighter tolerances on the mold.
413.1 creates a great looking part but it’s subject to more shrinkage defects than general grade aluminum, which could affect the castings mechanical performance. However, our engineers can predict in advance if these potential material defects will hinder your part’s performance.
As an example, we produce a gauge casting for measuring fluid flow. Initially we were using 356.1 general purpose aluminum that couldn’t fill the engraved lettering in the mold consistently, which resulted in a high scrap rate. Since the casting had low mechanical and structural requirements, we filled the lettering with ease using our 413.1 high fluidity aluminum.

319.1  LEGACY GRADE ALUMINUM

Before cutting technology improved, 356 general grade aluminum would stick to cutting tools, which is why 319.1 was widely used. 319.1 has higher iron content that made it easier to machine, but the higher iron content lead to more shrinkage defects, which made it more difficult to cast.
319.1 isn’t as common as it once was now that machining technology has advanced.

ZA-12 WEAR-RESISTANT ZINC ALLOY

Zinc is the material of choice amongst clients looking for wear resistance. ZA-12 is commonly used for hydraulic cylinder glands, sleeves, grippers, and any other application that requires high levels of wear resistance.
In addition, it has twice the density of aluminum, resulting in castings twice the weight.