Predicting mechanical property plateau in laser polymer powder bed fusion additive manufacturing via the critical coalescence ratio

The state of the art in property-process relationships laser polymer powder bed fusion (LPPBF) subcategory (PBF) has derived between energy supplied and thermal properties governing melting degradation, so-called “energy melt ratio (EMR).” EMR provides a framework for process parameter value selection based solely on behavior. However, coalescence, not merely melting, is basis mechanical LPPBF printed parts. authors present method (1) predicting coalescence transient temperature profiles resulting from combination values (2) connecting predicted response to observed onset plateau properties. This work tests hypothesis that property corresponds with transition consolidation physics. Complete must be achieved prior physical gelation. For this work, situ were obtained using infrared thermography. Coalescence prediction, via Upper-convected Maxwell model, gelation Lauritzen-Hoffman Avrami equations, found successfully identify combinations parts density tensile strength inside region. occurs at closed pore morphology supported.