Farzad Liravi, Graduate Student, University of Waterloo
Ehsan Toyserkani PhD, PEng, Professor, University of Waterloo
Conventional manufacturing techniques, such as molding, are widely used for production of silicone-based prostheses by clinicians. These techniques are time-consuming, expensive, uncomfortable for the patients, and lack customization. Developing additive manufacturing (AM) techniques for fabrication of complex silicone structures can revolutionize the prosthetics industry. In comparison to other polymers, high viscosity and thermosetting properties of silicone make it difficult to develop a robust technique for 3D printing of complex structures. Hence, so far proposed methods for silicone 3D printing, have been mostly limited to the production of a few layers of a simple geometry rather than a complex heterogeneous shape. We have deployed a customized multi-head 3D Printer, including two pneumatic material extrusion and three piezoelectric material jetting heads for fabrication of bio-structures. The new generation of jetting systems makes the dispensing of viscous fluids possible by combining air pressure with the force generated by reverse piezoelectric effect and their high frequency increases the printing speed. Combining multiple nozzles results in fabrication of heterogeneous structures composed of different silicones. This study includes the preliminary results of the proposed technique as well as the detail of statistical experiments conducted to improve the surface quality and physical properties of the printed parts.