Why 304 Stainless Steel Shot Is Ideal for Aluminum Die Casting

Moderate hardness to protect the substrate

Aluminum alloy die-castings are relatively soft. Using abrasives that are too hard—such as certain types of cast iron or high-carbon steel shots—can easily leave deep impact marks or even cause deformation. 304 stainless steel shots have a relatively moderate hardness and a gentler impact, allowing for the removal of burrs and oxide scale while preserving the dimensional accuracy and surface flatness of the workpiece.

Achieving a refined matte finish

304 stainless steel shots are typically spherical and offer excellent flowability. After processing, they impart a uniform, refined matte metallic finish to the aluminum alloy surface. This texture not only enhances the product's aesthetic appeal but also effectively masks minor surface defects, such as fine scratches or "crazing" (cracks) resulting from the die-casting mold. This is particularly crucial for 3C (consumer electronics) products or hardware components that demand a high-quality appearance.

Preventing iron contamination and rust

Aluminum alloys do not rust on their own; however, if standard steel shots are used, residual iron particles can lead to the development of rust spots on the workpiece later on. 304 stainless steel shots, by contrast, offer superior oxidation and corrosion resistance. They leave the workpiece surface free of rust and discoloration, often eliminating the need for subsequent cleaning steps like acid pickling, thereby streamlining the production process.