The Impact of Cooling Rate on Casting Quality

When aluminium or zinc fills the die, it’s not just about getting the metal in — it’s about how the metal cools.

The cooling rate plays a crucial role in determining the mechanical properties, surface finish, and dimensional stability of the final casting.

⚙ What happens with fast cooling?

✅ Finer grain structure → higher strength

✅ Lower porosity

✅ Better dimensional accuracy

⚠️ But too fast can cause internal stress, hot tearing, or distortion.

⚙ What happens with slow cooling?

✅ Lower internal stress

✅ More uniform solidification in thicker sections

⚠️ But may lead to coarse grains → lower strength

⚠️ Higher risk of shrinkage porosity

🌡 Factors that influence cooling rate:

• Die temperature (preheating and cycle management)

• Alloy type (different alloys solidify at different speeds)

• Wall thickness of the part

• Die cooling system efficiency

  
  

💡 LVIO Precision’s role:

LVIO works with simulation tools to specify and validate casting cycle and cooling strategies that suit the part geometry and alloy. This ensures the casting arrives at our CNC lines in a condition that meets both dimensional and mechanical specs — ready for precision machining and finishing.