Why Coat Die Cast Tooling?
PVD coatings like CrN are often used in die casting for several reasons. “Soldering” happens when molten aluminum attacks the H13 tool steel and leaches the iron out of the steel. This makes core pins and cavities look like swiss cheese from depletion of the tool steel. PVD coatings offer a hard, smooth barrier which prevent the molten aluminum from reaching the steel. This creates a much better system for keeping your mold components in perfect shape.
Erosion, or Washout are two of the other main problems associated with die cast tooling. Coating are especially helpful around high wear areas like gates. PVD coatings have the highest possible hardness to combat the abrasive properties of high velocity aluminum.