Local evaluation of metal laser powder bed fusion layer-related characteristics using a metrological XCT-based methodology

A metrological approach is proposed for local evaluation of effective layer thickness, powder bed density, and actual volumetric energy density in metal laser powder bed fusion. A custom-built plate with removable inserts enables robust alignment and accurate single-layer analysis through high-resolution metrological X-ray computed tomography (XCT). Effective layer thickness and powder bed density are determined through specifically developed procedures, allowing calculation of actual energy input. Results reveal significant deviations from nominal values and reduced energy efficiency. The method also quantifies the influence of other process-related phenomena, such as spatter formation and denudation on layer formation, offering deeper insights into process stability and efficiency.