Spray‐Assisted Microwave Welding of Thermoplastics Using Carbon Nanostructures with Enabled Health Monitoring

Abstract

The present study considers the use of spray‐assisted hybrid microwave welding using suspensions with low concentration of carbon nanostructures (CNS) (0.01 wt%). The proposed method of joining allows to create micron level coverage of the CNS on the thermoplastic substrates using a spray deposition technique. Upon electromagnetic microwave exposure, the CNS coverage provided structural joining of the parts due to dielectric heating. Small clamping force was applied to introduce uniform contact between the welded substrates. The choice of CNS was based on the superior dielectric loss and storage properties when compared to conventional carbon nanotubes. Furthermore, the proposed method of bonding allowed the creation of an electrically conductive percolated network at the welded interface, which was used for structural health monitoring by detecting the changes in the electrical resistance during single lap joint mechanical testing. The proposed method was shown to provide structural levels of welds for thermoplastic with different molecular structure, namely polycarbonate, polyurethane and high‐density polyethylene. POLYM. ENG. SCI., 59:2247–2254, 2019. © 2019 Society of Plastics Engineers

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