A Droplet Generator Using Piezoelectric Ceramics to Impact Metallic Pellets

Area of Science:

• Materials Science and Engineering
• Microfabrication Technologies
• Additive Manufacturing

Background:

• Metal micro-droplet ejection is crucial for micro-metal part prototyping and microelectronic packaging.
• Current technologies face challenges including specialized environments, complex feeding, and high costs.

Purpose of the Study:

• To design and analyze a novel drop-on-demand droplet generator for metallic pellets using impact feed ejection.
• To develop a cost-effective and structurally simple device for atmospheric micro-droplet ejection.

Main Methods:

• A micro-channel feeding method utilizing piezoelectric ceramic actuators.
• Rigid dynamics modeling of metallic pellet flight trajectory.
• Computational Fluid Dynamics (CFD) simulation using Fluent to analyze melting and ejection processes.

Main Results:

• Stable droplet generation with a 500 µs pulse width and 1100 mm/s initial velocity.
• Simulation reveals feeding, melting, and ejection stages taking 39.5 ms, 7.85 ms, and 17.65 ms, respectively.
• Projected injection frequency of 15 Hz for the metal projectile droplet-generating device.

Conclusions:

• The developed droplet generator offers a simplified, compact, and cost-effective alternative for metal micro-droplet ejection.
• The device operates effectively in an atmospheric environment, eliminating the need for micro-oxygen conditions.
• This technology shows promise for advancing rapid prototyping and microelectronic packaging applications.