Effects of Powder Characteristics of Different Alloy Powders from Different Manufacturers on Part Quality in Area Printing™

Conference Abstract: Additive manufacturing using laser-powder bed fusion (LPBF) has experienced significant growth in recent years, enabling the fabrication of various metals and alloys. However, LPBF's intrinsic limitation of low manufacturing speed has hindered its adoption in conventional manufacturing methods. Large-area pulsed laser powder bed fusion (LAPBF), also known as "Area Printing™" developed by Seurat Technologies, has addressed this limitation by replacing the point laser in the conventional LPBF with a large-area pulsed laser. Each pulse selectively melts a region of the powder bed in the order of square millimeters, operating at 40 Hz repetition speed, which enables scalability without the sacrifice of resolution and high throughput at an equivalent or better quality (in part due to a lack of spatter) when compared to conventional LPBF methods. As the LPBF technology has transitioned from prototyping to end-use parts, understanding the role of the powder properties needed to produce parts of acceptable quality reliably becomes critical. In this study, different alloy powders from different metal powder manufacturers are tested for flowability, spreadability, particle size distribution, and sphericity. The tested alloys include stainless steel 316L, Nickel-based super alloy 625 (Inconel 625), M300 maraging steel (also known as Tool Steel 1.2709 and 18Ni300), and Ti6Al4V. These powders were then used as feedstock in the Area Printing process to print density cubes and correlate the powder characteristics to parts density. The results suggest a strong correlation among the powder characteristics and between these characteristics and the density of the parts. Also, the observed Area Printing process sensitivity to the powder feedstock's properties is higher than what is reported in the literature for the conventional LPBF process, which is attributed to significantly different melt pool aspect ratios in Area Printing.