**Morgan Letenneur, Alena Kreitcberg and Vladimir Brailovski \***

Department of Mechanical Engineering, École de technologie supérieure, 1100 Notre-Dame Street West, Montreal, QC H3C 1K3, Canada; morgan.letenneur.1@etsmtl.net (M.L.); alena.kreitcberg.1@ens.etsmtl.ca (A.K.) **\*** Correspondence: vladimir.brailovski@etsmtl.ca; Tel.: +1-514-396-8594

Received: 18 December 2018; Accepted: 12 February 2019; Published: 21 February 2019

**Abstract:** A simplified analytical model of the laser powder bed fusion (LPBF) process was used to develop a novel density prediction approach that can be adapted for any given powder feedstock and LPBF system. First, calibration coupons were built using IN625, Ti64 and Fe powders and a specific LPBF system. These coupons were manufactured using the predetermined ranges of laser power, scanning speed, hatching space, and layer thickness, and their densities were measured using conventional material characterization techniques. Next, a simplified melt pool model was used to calculate the melt pool dimensions for the selected sets of printing parameters. Both sets of data were then combined to predict the density of printed parts. This approach was additionally validated using the literature data on AlSi10Mg and 316L alloys, thus demonstrating that it can reliably be used to optimize the laser powder bed metal fusion process.

**Keywords:** additive manufacturing; laser powder bed fusion; process optimization; analytical model
