Feasibility of Melting NbC Using Electron Beam Powder Bed Fusion

Abstract

High melting point materials such as ceramics and metal carbides are in general difficult to manufacture due to their physical properties, which imposes the need for new manufacturing methods where electron beam powder bed fusion (EB‐PBF) seems promising. Most materials that have been successfully printed with EB‐PBF are metals and metal alloys with good electrical conductivity, whereas dielectric materials such as ceramics are generally difficult to print. Catastrophic problems such as smoking and spattering can occur during the EB‐PBF processing owing to inappropriate physical properties such as lack of electrical, and thermal conductivity and high melting point, which are challenging to overcome by process optimization. Due to these difficulties, a limited level of understanding has been achieved regarding melting ceramics and refractory alloys. In this work, three different substrates of niobium carbide (NbC) were melted using EB‐PBF. The established process parameter window showed a good correlation between EB‐PBF process parameters, surface and melt characteristics, which could be used as a baseline for a printing process. Melting NbC was proven feasible using EB‐PBF, the work also pointed out challenges related to arc trips and spattering, as well as future investigations necessary to create a stable printing process.This article is protected by copyright. All rights reserved.