Homogenization methods for thermal study of support structure in laser powder bed fusion (L-PBF) – application to process numerical modeling

Abstract

Purpose

This paper aims to report on a homogenized model for the anisotropic thermal conductivity of support structures constructed by the laser powder bed fusion (L-PBF) process, and its application to the numerical simulation of the L-PBF process.

Design/methodology/approach

Considering both analytical and numerical approaches, the model is developed across a temperature interval encompassing the entire L-PBF process. Subsequently, the homogenized material properties are incorporated into a thermal finite element model (FEM) of the L-PBF process to consider the effects of the support structures, taking into account their anisotropic properties.

Findings

The simulation results of the L-PBF process indicate that the support structures act as a thermal barrier, retaining more heat in part compared to direct printing on the substrate. The implementation of homogeneous thermal conductivity in the L-PBF process simulation demonstrates its efficiency and potential application to better control heat transfer during part construction.

Originality/value

The homogenized anisotropic thermal conductivity of a support structure has been characterized by both analytical and numerical approaches. Such homogenized anisotropic tensor was implemented in L-PBF numerical simulation. This showed a strong influence of the supports on the temperature distribution and evolution.