Dry ice blasting
Dry ice pellets are solid carbon dioxide pellets that sublimate on impact and release thermal energy. They clean the metal residue-free without damaging it.
Physical-Chemical Mechanism of Action
Dry ice blasting consists of solid CO2 pellets that sublimate on contact with air. This process releases a significant amount of thermal and kinetic energy that effectively cleans the metal.
Metallurgical Relevance & Welding Risks
Dry ice blasting is especially useful for cleaning weld areas. It removes dust, oil, and other contaminants without damaging or altering the base metal. However, incorrect application can lead to incomplete cleaning, which can cause weld defects like porosity or lack of toughness.
Shop Practice & Action Guidelines
Use dry ice blasting as follows:
1. Make sure the metal is dry and free of dirt.
2. Spray the pellets onto the area to be cleaned.
3. Let them sublimate until no pellets are visible.
4. Check the cleaning with an air nozzle or a microscope.