To test the strength of a forged aluminum wheel versus a fabricated steel wheel, we recently conducted an impact test. Historically, these impact tests have been used to test cast aluminum wheels, for which they do not fare well.
To best understand the results of the impact test, it is important to understand how wheels are made and understand both their characteristics and properties.
The different type of wheels and how they are made:
The following is background on the differences between various type of wheels and what sets each apart in the industry. Today, there are three different types of wheels on the market:
- Cast aluminum wheels
- Fabricated steel wheels
- Forged aluminum wheels
A cast aluminum wheel is typically made of A356 aluminum alloy and manufactured similarly to Jell-o. A molten product is placed into a mold and following the process, creates a raw casting. It then goes through multiple, additional processes including an x-ray, which is most important. This is critical as the casting process contributes to porosities and inclusions that can be detrimental to the final product. Therefore, the x-ray process allows the operator to understand whether the porosity is the right size and in the right location so as not cause any issues. There are additional steps taken including running through a high temperature thermo process which allows the product’s final strength to be achieved. Finally, it transitions to machining, and then ultimately to finishing which results in either the part being polished or painted.