Examining Semi-Solid Aluminum Casting and the SEED Process

Despite significant technical and economic advantages semi-solid metalcasting (SSM) has never advanced to become the major metalcasting process anticipated by so many early investigators. Still, there are still several positive indicators of the value of semi-solid casting for aluminum alloys, as detailed by Pascal Côté, Giovanni Pucella, and Steve Midson in their report, The Benefits of Semi-Solid Casting for Aluminum Alloys.

Proceeding from the proposition that there are multiple advantages to producing castings in uncoated metal molds (including surface finishes, close dimensional tolerances, and fine-scale microstructures, due to rapid heat extraction) they address the challenge of high-cooling rates and solidification irregularities with existing semi-solid metal casting technologies.

The Swirled Enthalpy Equilibration Device (SEED) process they introduce represent a new possibility for high-volume, high-productivity, thin-walled casting production. It is a technically advanced and economically successful rheocasting processes that minimize turbulence during the production of the semi-solid slurry — making it effective for producing high quality castings. It optimizes metal quality during both the production of the slurry and during the casting process itself, and may represent the future for semi-solid casting production.