Optimizing the Thermoplastic Welding Properties in an FRTPC Additive Manufacturing Process
M. Eichenhofer, S. Arreguin
Eidgenössische Technische Hochschule Zürich, Zürich, Switzerland
J.C.H. Wong, University of Calgary, Calgary, Canada
P. Ermanni, Eidgenössische Technische Hochschule Zürich, Zürich, Switzerland

Abstract:
Additive manufacturing enables a flexible route for producing low volume parts with high geometrical complexity. The layered nature of most additive manufacturing processes results in anisotropies in the built structures, regardless of whether the base materials used are isotropic, e.g. metals, or anisotropic, e.g. fibre reinforced polymer composites (FRPC). This phenomena is particularly apparent when characterizing the mechanical properties of AM parts along the build- or z-direction. Therefore, AM processes must be optimized to maximize the mechanical strength in the build direction in order produce mechanically robust parts. This study systematically investigates the thermoplastic bonding process that governs the interlaminar bonding properties for additively manufactured continuous fibre reinforced thermoplastic polymer composites (FRTPC). A design of experiments analysis shows a high dependence of the interlaminar shear strength and peel strength on the weld temperature and weld time. The test results for the best parameter configuration revealed a maximum shear strength of 14.79 MPa, representing 59% of the maximum shear strength measured under compression moulding conditions.