Predictable and precise porosity quantification in PBF-LB/M materials using automated optical microscopy

Accurate and objective porosity quantification is critical for Powder Bed Fusion-Laser Beam/Metal (PBF-LB/M) materials. This study compares the standardized Archimedes method against a simple automatic optical microscopy (OM) protocol for measuring porosity in copper alloy PBF-LB/M components. Across all trials, Archimedes reported porosity values atleast 1.3% higher than OM on paired samples and showed high, nonlinear measurement variability with mean porosity. In contrast, the OM protocol, utilizing rigorous sample preparation and a fixed-threshold analysis, provided superior consistency. OM results exhibited a strong linear correlation between measured porosity and measurement standard deviation ([Formula: see text] up to 0.92), demonstrating that its variability is structurally related to the actual porosity level. The proposed OM method offers a robust, predictable, and precise tool for R&D and quality control of additively manufactured components.