Dr. Rebecca Ruckdashel, Research Engineer III – Textiles, FASTR Lab, Advanced Structures and Composites Center, University of Maine

Additive manufacturing part strength is limited by the bonding between layers. This work sought to improve bonding between a printed thermoplastic resin and fabric during additive manufacturing, a.k.a. the first deposition layer. A preliminary print revealed the fabric construction, print temperature, and print speed may impact print adhesive strength. In the second print, three fabrics (laminated green canvas fabric, PET Knitted Moss Fabric, and PET Knitted Pique Fabric), two temperatures (220 oC and 240 oC), and four print speeds (1, 2, 3, and 4 m/min) were considered. These parameters impacted print quality and adhesive strength, determined by peel testing. Overall, the adhesive strength was far higher for the laminated green canvas fabric than for the knits. This is likely due to welding between the printed PETG-GF and the lamination. To a lesser extent, adhesive strength was improved by warmer print temperature and slower print speeds. Future work could consider other ways to improve adhesion – increasing temperature or increasing contact between fabric and printed material.