In flow-forming, a cylindrical preform is fitted over a mandrel. After both are made to rotate, compression forces are applied to the outside diameter of the preform by three CNC-controlled rollers. The desired geometry is achieved when the outer diameter and the wall of the preform are decreased and the available material volume is forced, through plastic deformation, to flow longitudinally over the mandrel. Typically, the preform can be flow-formed four to six times compared to its starting length before needing re-annealing.
As a cold forming process, flow-forming often achieves mechanical properties and dimensional accuracies that are far closer to requirements than can be achieved by warm or hot forming manufacturing processes and chip removal forming process. The flow-form process causes the material's mechanical properties to increase while refining the microstructure, orienting the crystallographic texture, and in some cases causes desirable metallurgical phase transformations. The flow-form wall reduction is engineered to achieve specific, material properties thru the cold work.
The flow form process creates a more compressed and dense wheel that requires less material, boosting weight reduction.
Compressed and elongated, the make up of the material allows it to be more impact resistant resistant than conventionally cast wheels.
When combined, the lighter and stiffer attributes of the wheel births a strong, high performance wheel.