Development of a CO2 snow jet blasting strategy for controlling the thermal influence on the substrate

The utilization of CO2 snow jet blasting in precision engineering applications has gained significant interest due to gentle substrate treatment and effective cleaning capabilities. This study investigates the thermal influence of CO2 snow jet blasting on the substrate and strategies to control it. CO2 snow jet blasting contaminate removal works through a combination of mechanical impact and thermal shock. As the pressurized liquid CO2 exits the nozzle, it forms CO2 snow particles. These particles are further accelerated by a compressed air jacket. The CO2 snow particles impact the surface at high velocities vs, dislodging contaminants. The rapid temperature reduction Δϑ induces thermal stress σT between the contaminants and the substrate, assisting in contaminant removal. This also induces thermal gradients ∇ϑ and thermal stress σT within the substrate. Extended exposure durations te result in more substantial temperature reductions Δϑ. Cleaning experiments were conducted while simultaneously tracking the temperature ϑ in relevant areas. Different cleaning strategies and process parameters were varied. The findings enhance the understanding of thermal behaviors in CO2 snow jet blasting and provide insights for improving precision cleaning processes in advanced manufacturing.