Optimizing Metal Powders for Additive Manufacturing

AM offers certain specific advantages relative to alternative powder metallurgy methods, ranging from design flexibility to the potential for high material use efficiency, and is particularly suitable for the production of small to medium volumes of relatively small components, as well as enabling the creation of totally new complex parts that were previously unachievable. The development of AM machines is an important area of focus as the technology is adapted to produce larger components, and deliver higher throughputs. However, there is now equal emphasis on the properties of the powders used. Up to one third of the production cost of an AM component is the cost of the powder used, with commercial viability resting on establishing a robust supply chain and effective powder recycling strategies. Identifying analytical tools that can be used to reliably set specifications for AM metal powders to validate quality and manage their use is vital. In this white paper, we review the key processes used in AM and how they determine the requirements of metal powders for this application. Case study data from the National Centre for Additive Manufacturing, part of the UK’s Manufacturing Technology Centre (MTC, Coventry, UK), highlights the value of particle size and shape, powder flowability and bulk density measurements in the selection, optimization and management of AM powders.