Thicker Die Casting Walls, Stronger Part, No
Kinetic Die Casting Company has helped many customers develop new products. There are many factors singular to the die casting process that are needed to consider such as product strengths, draft angles, gate areas, material types, material flow, slide features, undercuts, and wall thicknesses.
Over the years, I have had to convince several buyers, engineers, and designers that increasing the thickness of the walls or other sections in a die casting part does not increase the part strength. In fact, it does the opposite. As the molten metal is injected through the gate, into the die casting mold, the metal freezes on the wall surfaces of the die on the die casting part exterior and interior. The metal contacting these die surfaces is denser and harder than the section sandwiched between the two wall surfaces.
The first .030” to .050” surface of the casting where the metal is denser is commonly called the “skin” of the die casting. The die casting skin is on both interior surfaces and exterior surfaces. The material between the two skin surfaces is weaker and less dense. A part that has a wall thickness of .080” would have a skin surface of about .060”, on the interior wall .030” and the exterior wall .030”. The section sandwiched between the two skins, approximately .020” would provide little strength.
Die Casting parts should not typically be thicker than .125”. On die casting parts with thicker walls than .125”, the increased thickness decreases the wall strength by increasing opportunities for porosity, shrinkage and laps. Parts that will be machined should only have less than .030” removed to preserve more of the die casting strength and to avoid exposing porosity.
When it comes to increasing strength in aluminum die casting parts, other methods are used. I will detail how to strengthen die casting parts in future articles.
Contact Kinetic Die Casting Company 800-524-8083, if you have a metal product that you are considering manufacturing. We will evaluate your design and make suggestions on other metal manufacturing processes when necessary. If die casting is the best option, we will assist you in material selection, tooling manufacture, and provide the cost for tooling and die casting parts.
Tags: Aluminum Die Casting, Casting Metal, Die Casting Part Design
