Conventional and Flash Sintering of Research Objectives Tungsten and Tungsten Alloys Prepared • Robocasting at room temperature avoids the steep thermal gradients and resulting residual stress of the current SOA: powder bed fusion and flash sintering greatly decreases the by Robocasting of ALD-doped Precursors sintering time and furnace temperature • PI: Alan Weimer, University of Colorado Boulder Use ALD to uniformly distribute additives throughout W powder to improve final microstructure Co-I: Rishi Raj, University of Colorado Boulder • Flash sinter green bodies Collaborators: to achieve high final James F. Smay, 3D Inks, LLC density Arrelaine A. Dameron, • This project will bring Forge Nano the technology from TRL 2 (speculative) to TRL 3 by proof of concept of Approach high density, high • Coat W powder with strength AM tungsten sintering aids or beneficial parts from ALD powder dopants • Formulate gel colloidal inks from W powder Potential Impact • Robocast samples for both • Flash sintering of ALD conventional and flash coated W will greatly sintering reduce the required • Sinter samples and processing time of AM characterize final density, refractory materials surface roughness, • We expect that the uniform dispersion of alloy additives and sintering aids will improve • microstructure, strength, chemical composition, pinning of grains and inhibit growth to improve final mechanical properties of AM parts and contact angle including tensile yield and ultimate strength • To modify hydrophobicity, add external ALD coating • This success will enable AM of tungsten parts for high temperature applications such as and test using the sessile drop method NTP engines, re-entry systems, and terrestrially in nuclear reactors and jet engines