Microwave Induced Welding of Carbon Nanotube-Thermoplastic Interfaces for Enhanced Mechanical Strength of 3D Printed Parts

Additive manufacturing or 3D printing is a burgeoning method for manufacturing mechanical components; these parts however, are typically not intended for load-bearing use due to incomplete bonding between successively deposited layers. We report a novel method for improving the bond strength of 3D printed thermoplastic interfaces using intense localized heating of carbon nanotubes (CNTs) upon microwave irradiation. The microwave heating mechanisms of CNT-polymer composites were thoroughly investigated by analyzing the microwave dielectric properties of a range of CNT contents both above and below the percolation threshold. These results were coupled with in-situ thermal imaging of the composites during microwave irradiation and validated with computational simulations.