(230d) Aerosol-Based 3D Printing to Improve Resolution and Simplicity

3D printing additive manufacturing processes have made prototyping and manufacturing easier and quicker due to their cost-effectiveness, automation, and capacity to produce complex structures. There are numerous 3D printing techniques currently available, such as fused deposition modeling, powder bed fusion, stereo-lithography, and others. Essential characteristics to consider for a 3D printing process are – resolution (capability to print small dimensions), versatility (capability to print a wide variety of materials and is easy to use), and speed (single step and high throughput). The existing techniques limit in at least one of these characteristics. Fused deposition modeling, for instance, is easy to operate but can only print polymers and has a maximum resolution of 100 μm, which is also hard to achieve. Powder bed fusion, a common technique for 3D printing metals, is complex and requires a high-power laser to melt the particles and a special enclosure to create a stable particle bed for printing, but it still lacks high resolution (< 50 μm). Moreover, stereo-lithography has good resolution but can only print photocurable polymers.

A simple aerosol-based 3D printing (A3DP) process that can print a wide range of materials at small-length scales (< 50 μm) and without requiring any special environment during printing will be discussed. While there are some aerosol-based printing methods (e.g., aerosol jet printing), our A3DP technique prints particles that are melted in the printing nozzle (and not on the surface). The A3DP method is a particle-based 3D printing method to create the structure. In this process, the feed material is aerosolized and introduced into the printer. The aerosolized droplets are dried, generating solid particles. The particles melt inside the nozzle that translates on the printing surface and prints the aerosols. The aerosol-based 3D printing takes advantage of the continuous aerosol process and combines it with 3D printing to achieve high-resolution continuous printing with precise control over the properties of the deposited structure. Examples of printed 3D structures with polyethylene glycol with a resolution of 41 μm will be described. Additionally, the feedstock can be controlled at any time to obtain the desired resolution and material. The ability to generate size and composition-controlled particles and their subsequent printing makes it easy to 3D print small dimensions. Currently, we are designing the printing nozzle by simulating the particle printing in COMSOL Multiphysics and developing sync between the particle generation and printing process to print structures with high precision and resolution.

The talk will discuss the role of several important process parameters, such as nozzle temperature, printing surface temperature, and nozzle-to-printing surface distance. This impact phenomena such as fluid flow, particle size, particle velocity, melting of materials, melting and solidification rate, eventually affecting the print resolution and quality. This simple, continuous, and high-resolution 3D printing technology can help print complex structures requiring high-resolution, such as microdevices for biomedical, military, and space applications.

Reference

Kavadiya and Biswas (2023), Improving the resolution and simplicity through aerosol-based 3D printing, in preparation