Heat treatment effects on fracture resistance of additively manufactured PLA specimens under mode I loading
M.R. Ayatollahi, Parham Rezaeian, A. Nabavi‐Kivi, Mohammad Reza Khosravani
Abstract
Abstract The current paper deals with the influence of heat treatment on the tensile, flexural, and fracture strength of polylactic acid (PLA) specimens made by the fused deposition modeling (FDM) technique. Three different temperatures of 80°C, 100°C, and 120°C were used to anneal the dog bone and enlarged compact tension (ECT) specimens to examine the mechanical and fracture performance of the FDM‐PLA parts, respectively. The fracture behavior was assessed using the equivalent material concept (EMC) combined with the J‐integral, average strain energy density (ASED), and maximum tangential stress (MTS) criteria, and the theoretical estimates were compared with the experimental results. Finally, the effectiveness of these criteria was discussed comprehensively, and the failure mechanisms in the broken tensile and flexural specimens were investigated using scanning electron microscopy (SEM). Overall, applying heat treatment to the FDM specimens could improve their structural integrity by around 57% from the fracture resistance point of view.