Hard drive case grading

Cast is the best grade for selling HD chassis to the yards, but they are actually forged in their manufacture. A hot short, slug of extruded Aluminium is sandwiched between a set of dies under massive pressure,to form the basic shape. Then the critical surfaces are machined in after the coating has been applied.



They are forged from extruded Ali to avoid any defects in the grain structure that is common in cast items. A give away is the surface texture of the chassis, too smooth to be a cast item. Some yards may try to tell you they are die cast (implying a zinc content), but its not. Neither does it have the silicon content in the alloy that allows the molten metal to flow into those tight shapes and corners. They are forged from extruded slugs of pure Aluminium.