Investigation of the vector length as an influencing variable on the chemical composition in powder bed-based fusion of metals using a laser beam

Abstract

Powder bed fusion of metals using a laser beam (PBF-LB/M according to DIN EN ISO/ASTM 52900) is an established additive manufacturing process for the direct production of metallic components. This process is subject to influencing variables which significantly affect the properties of the manufactured component. Scanning speed, laser power and hatch distance are decisive for the production of melt tracks that result in sufficient wetting and a dense component. In order to determine a suitable parameter window, samples made of AlSi10Mg with a defined vector length are manufactured and evaluated in qualification processes. This article examines the influence of the vector length on the component properties, such as hardness, density and chemical composition. The question arises as to whether qualified vector lengths can be scaled to any length without further investigation and without impairing the component quality. With the help of energy-dispersive X-ray fluorescence analysis (EDXRF) and energy-dispersive X-ray spectroscopy (EDX), it was possible to detect a fluctuation in concentration for the element aluminum. The samples show a change in chemical composition depending on the vector length, detected with EDXRF. However, a correlation between the chemical change resolved locally along the vector length cannot be determined yet.