Investigation of Crucial Properties for Polymeric Recoater Materials in Metal Additive Manufacturing
Abstract
Laser powder bed fusion metal additive manufacturing creates parts using layers of powder dispersed across a build area that are then selectively melted by a laser. In this iterative process the dispersion of the powder layers is done by a recoater. The uniformity and consistency of the powder dispersion is critical to part performance, properties, and geometric accuracy. The recoater is responsible for distributing powder across the build area. The recoater assembly typically consists of a rigid arm with a replaceable insert. The insert can come in many forms, some examples being metal blades, elastomeric rods or wipers, or hard ceramics. As the recoater arm moves across the build area the gap between the recoater and the build material needs to be uniform to prevent inconsistencies in powder dispersion. If the recoater is damaged or wears away due to interactions with the print, this gap thickness can change heterogeneously across the width of the recoater and result in premature build failures and/or defects in the printed parts. This study investigated the influence of the hardness and size of polymeric recoater materials on the height deviations in the recoater at varying build heights. It was found that the maximum height change of the recoater increases with decreasing hardness. No consistent trend between recoater size and maximum height change or the rate of height change was found. After testing, our team has decided to begin using a harder recoater, as it showed the least amount of height deviation and showed consistent trends regarding height change and build height. This will allow for more confidence in our process and reduced build failures, especially with very long build times.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 08, 2023
- Accession Number
- AD1196023
Entities
People
- Alex Butler
- Brandon McWilliams