Quantitative Characterization of Metal Powder Morphology, Size Distribution, and Flowability for Additive Manufacturing

The properties of the powder utilized in powder bed-based additive manufacturing are crucial in determining both the process parameters and the final quality of the fabricated components. Therefore, it is essential to assess powder characteristics, particularly particle morphology, size distribution (PSD), and rheological properties. This study aims to quantitatively characterize the PSD, morphology, and flowability of metal powders commonly used in additive manufacturing, such as AlSi10Mg, Inconel-718, Ti6Al4V, titanium, and stainless steel. To achieve this, we utilize a range of PSD models to accurately fit the measured size distributions based on volume and number, followed by conducting statistical analyses to determine the best-fitting models. Furthermore, we conducted a shape analysis using the elliptic Fourier series to characterize particle morphology quantitatively. Additionally, we examined the correlations between the powder rheological properties, measured by a Hall flowmeter, tapped density tester, and FT4 powder rheometer, and the PSD and shape indices using Spearman's coefficient test.