Effects of Atomization Injection on Nanoparticle Processing in Suspension Plasma Spray

Area of Science:

• Materials Science
• Plasma Physics
• Chemical Engineering

Background:

• Liquid atomization is crucial for injecting nanoparticle suspensions into plasma torches for dense coating applications.
• Understanding atomization parameter effects is key to optimizing nanoparticle processing in suspension plasma spray (SPS).

Purpose of the Study:

• To investigate the influence of liquid atomization parameters on nanoparticle behavior during suspension plasma spray (SPS).
• To develop a numerical model simulating droplet, nanoparticle, and plasma gas interactions.

Main Methods:

• Developed a numerical model to simulate droplet and nanoparticle dynamics within a turbulent plasma jet flow.
• Tracked discrete Lagrangian entities for droplets and nanoparticles, analyzing their motion and thermal histories.
• Investigated the effects of droplet size, injection angle, and velocity on nanoparticle release and melting.

Main Results:

• Smaller droplet sizes and reduced nanoparticle aggregation in the suspension preparation are preferred for optimal SPS processing.
• Injection angle and velocity critically affect nanoparticle release percentages; lower velocity and smaller angles promote release.
• A critical droplet diameter for complete nanoparticle melting was determined, dependent on agglomerate size and suspension weight content.

Conclusions:

• Effective nanoparticle processing in SPS relies on controlled atomization, favoring smaller droplets and less aggregation.
• Optimized injection parameters can enhance nanoparticle release, while agglomerate size dictates melting completeness.
• Limiting suspension droplet size is essential for achieving high-quality dense nanostructure coatings.