Forged vs Flowform Wheels - Why we choose Forged Aluminum over all
So, you want a racing wheel, a performance wheel for your car or truck and the internet is throwing terms at you like - forged, flow formed, rotary formed, flow forged and on and on. If you are confused, don’t feel bad. Wheel companies have realized that “cast” is a dirty word these days and on a marketing level, they are “muddying the water”. We are here to explain the difference between Forged vs Flowform Wheels and why 3030 Autosport only offers forged wheels.
And even better, we’ll make it quick and simple.
The Structural Difference Between Cast Wheels and Forged Wheels:
Take a piece of particle board (you know, the powder-wood they make cheap furniture from). It’s very porous and has no grain structure like real wood does. Now slam it on a driveway. What happens? It shatters. It fails catastrophically and immediately. Consider this an example of how a cast wheel fails.
Now take a wooden baseball bat. With all its grain structure intact. Slam the bat on the driveway. What happens? The bat is totally intact, and you now have a sore arm. Consider that an example of forged aluminum and why it is insisted upon for racing, aerospace, and military applications where failure is not an option.
Cast Aluminum - Higher in weight, lower in quality...
When metal is melted and casting is produced, a product of complex shape can result, only limited by the mold making and the flow and solidification dynamics of the metal. The disadvantage is the potential for contamination while metal is in a liquid state from impurities entering into the liquid. Formed while ingots and additives are being melted, impurities may not be sufficiently filtered from the liquid metal as it flows into the mold. Small pieces of the conduits leading to the mold or the mold itself can also flake or break, entering the liquid. Turbulence as liquid metal flows through complex chambers may result in voids and internal, hidden, areas of non-fill. Alloy segregation while the metal is in liquid form can result in inconsistent material properties from one area of the casting to another. Defects such as tears or cracks can form when different sections mass cools at different rates as the metal solidifies. Why would any wheel company offer a cast wheel? Simple - Cheap price.
So, What is Flow Form? (Aka – Flow Forged, Rotary Formed and Flow-forged)
Flow form wheels begin with a cast aluminum center (spoke) section with extra cast material that is spun out to create the rim section. While this process creates a lighter version of a cast wheel and is stronger in the rim section than a cast wheel, flow forming cannot compete with a forged racing wheel’s superior strength-to-weight ratio in the over-all wheel. For this reason, a flowformed wheel will be slightly lighter weight than a similar cast wheel yet much heavier than a forged wheel.
At the end of the day, every flowform wheel has a cast center section like every other cast wheel, and that is where all the stress happens in racing.
Forged Aluminum Wheels - the Strongest, and the Lightest...Period
Forging has the advantage of the addition of deformation energy to further refine and improve the metallurgy of the shape being created. Through mechanical and thermomechanical deformation energy applied, originally cast ingots of aluminum are shaped and reshaped, changing the internal microstructure. Any inclusions or alloy concentrations are dispersed, and any voids are crushed and eliminated. Forging energy drives the recrystallization of the microstructure, creating enhanced durability and toughness. The forging process is costlier however, the improved properties of forged product outweigh cost issues, however, when safety, reliability and the cost of component failure are the greatest challenges.
Because forged material is so dense and strong, less material is required to produce a wheel of equal or greater strength, resulting in a much lighter wheel.
We hope this very abridged and basic explanation helps clear up any confusion and get you to an informed decision.
Thanks for reading!
For more information from a 3rd party - here is a great article we found regarding both processes: