Die Casting Problems

Like any manufacturing process die casting is not completely perfect and errors occur. The way to prevent and catch them is by appearance and understanding the purpose of the piece. For instance, a diecasted product can have surface defects, internal defects, and dimensional defects.

Surface- how the product looks to the eye

  • Flow- how the metal is poured

Alloys can freeze before the casting is filled

Some alloys do not weld together



  • Blisters– Bubble like bumps

        Gases are trapped

  • Cracks– fissures in the product

Casting die or alloy is cold

Die is to hot

  • Soldering – melding of materials

Fusion of aluminum in die with melted alloy


Internal- affect machinability of product

  • Sludge- composed of left over minerals creating a hard spot

               Old die cast offs


  • Porosity – Smooth, circular bubbles

Trapped gas


Dimensional Defects – precision operating conditions

  • Contraction/Expansion- smaller/bigger formation
    • Dies castings are two different temperatures
    • Fixing the problem: Change Die temperature, alloy temperature, alloy being cast, wall thickness, fill time, flow distance, gate velocity, and venting