In blown powder Direct Metal Deposition (DMD) process, parts are built by adding metal powder on the melt pool created by the laser system. At low feed rates powder feeder systems have perturbations. The study focused on relationship between the perturbation frequencies by inherent powder feeder designs and its impact on deposition quality. Performance metric determine the relation between perturbations in the powder flow and quality of the deposit. To determine performance metric, various powder feeder designs were analyzed. Perturbation frequencies were introduced to the disk feeder design. The quality of the deposit was determined by the surface roughness of the deposit. A laser displacement sensor was used to measure the surface roughness of the deposits. Experiments were carried out to determine the significance between measured surface roughness values of the deposits over theoretically calculated performance metric values. Validation tests were done to compare the data fit. The wheel feeder and newly developed disk feeder were compared for deposit quality. The results showed better performance metric for the disk feeder system under the same process parameters. Based on this metric, a feeder system can be used to derive acceptable powder flow parameters given a minimum quality specification.
V. S. Bitragunta et al., "Performance Metric for Powder Feeder Systems in Additive Manufacturing," Proceedings of the 26th Annual International Solid Freeform Fabrication Symposium (2015, Austin, TX), pp. 473-491, University of Texas at Austin, Aug 2015.
26th Annual International Solid Freeform Fabrication Symposium -- An Additive Manufacturing Conference, SFF 2015 (2015: Aug. 10-12, Austin, TX)
Mechanical and Aerospace Engineering
Keywords and Phrases
Blown Direct Metal Deposition Process; Perturbation Frequency; Disk Feeders; Deposit Quality; Surface Roughness
Article - Conference proceedings
12 Aug 2015