An Ashby-like Database for Volumetric Energy Density in Additive Manufacturing Across Various Material Classes

Additive Manufacturing (AM) processes transform the world of materials science and manufacturing engineering through their unique capabilities. Several processing parameters are involved in any AM processes. These parameters continuously influence microstructural development and the mechanical properties of the materials. Among these processing parameters, four critical parameters – laser power, scanning speed, hatch spacing, and layer thickness - directly affect the materials’ properties. While these properties are combined, a new and distinct processing parameter has emerged – Volumetric Energy Density (VED). Variation of the VED led to microstructural changes, influencing the mechanical properties of the materials. Different material classes possess distinct sets of VED, which enabled the preparation of an Ashby-like graphical representation. Based on that representation, any researcher or industrialist will understand the processing parameters, including the energy input (VED). This parameter is expressed as a function of the melting temperatures of the material. This provides the range of VED over a range of melting temperatures for any material class, similar to the other Ashby-like diagrams, like Young’s modulus or the strength of the materials as a function of density. However, this energy input is highly material-specific and cannot reveal critical defects associated with AM processes. However, this VED model, with a large database, could be beneficial for predicting the appropriate working range. In this review article, we discussed several aspects of this critical processing parameter, VED, and its effects on different materials across various material classes.