Exploring bending behaviour of hybrid fabric-3D printed structures with infill and raster angle for functional applications

Purpose The purpose of this study is to investigate the bending behaviour of three-dimensional (3D) thermoplastic polyurethane (TPU) structures printed onto the fabric. Design/methodology/approach TPU parts with varying infill patterns and raster angles were 3D-printed onto both woven and knitted fabrics. The resulting hybrid structures’ bending behaviours were evaluated using three test methods: cantilever bending, three-point bending and circular compression. Besides, both sides of the hybrid structures were tested to capture the influence of test direction. Findings The fabric structure is effective on adhesion force and greater values were observed for woven fabrics. The infill structures, raster angle and test directions were observed effective on the bending behaviour of the hybrid structures. The 45° raster angle resulted in greater bending resistance in three test methods. For knitted fabric structures, gyroid infill generally exhibits superior bending resistance. A case of fabricating a personal elbow brace for cubital tunnel syndrome was also introduced. Originality/value This study provides experimental information about the effects of 3D printing parameters on the bending behaviour of the hybrid structures and supports the development of special-purpose designs with tailored functionalities for various applications.