In many processing steps, heat is applied to an item, affecting its dimensions and material structure. Cooling time is required in order to eliminate the possibility of overheating. This cooling window can be reduced if carbon dioxide snow or liquid nitrogen is used as the cooling agent.
Liquid Nitrogen
Reducing the temperature from +20 °C to -196 °C (ΔT = 216 degrees) requires 0.5-1 liter of liquid nitrogen per kilo of metal. Due to the risk of frost damage, liquid nitrogen must be handled like boiling water.
Dry ice
Around 0.2 kilos of dry ice per kilo of metal are needed to reduce the temperature by 98°C. Dry ice can be sprayed or applied as pellets.
