(Invited) In Situ x-Ray Diffraction during Processing Under Extreme Conditions

Abstract

Many materials are processed under extreme conditions to lock in desirable structural properties, such as metastable phases, appropriate morphologies, and defect concentrations, since these can result in wanted functionalities. Examples include splat cooling, rapid thermal processing (RTP), selective laser melting (SLM), and roll-to-roll (R2R) printing. Often the evolution of the crystalline phases that form during such extreme processing conditions are not known, and can take place through unexpected sequences, including the formation of metastable phases. Understating these phase sequences is important, since this can guide more optimal synthesis or reaction pathways, but can be challenging due to the extreme environments. We have developed X-ray diffraction and imaging approaches to following such phase and microstructure sequences in environments such as RTP (1,2,3), SLM (4,5), R2R printing (6) and hydrothermal growth (7). In this talk, I will describe our methodologies for these types of experiments and give examples of RTP used to form silver electrical contacts to silicon solar cells, hydrothermal growth of Mn-oxides and SLM of Ti-alloys. D. Fields, Md.I. Ahmad, V.L. Pool, J. Yu, D.G. Van Campen, P.A. Parilla, M.F. Toney, M.F.A.M. van Hest, Nature Comm. 7, 11143 (2016).VL Pool, B. Dou, DG Van Campen, TR Klein, FS Barnes, SE Shaheen, Md. I. Ahmad, M.F.A.M. van Hest, MF Toney, Nature Comms 8, 14075 (2017).I. Ahmad, D.G. Van Campen, J.D. Fields, J. Yu, V.L. Pool, P.A. Parilla, D.S. Ginley, M.F.A.M. Van Hest, M.F. Toney, Rev. Sci. Instrum. 86, 013902 (2015).P. Calta, J. Wang, A.M. Kiss, A.A. Martin, P.J. Depond, G.M. Guss, V. Thampy, A.Y. Fong, J. Nelson Weker, K.H. Stone, C.J. Tassone, M.J. Kramer, M.F. Toney, A. Van Buuren, M.J. Matthews, Rev. Sci. Instrum. 89, 055101 (2018).“Dynamics of pore formation during laser powder bed fusion additive manufacturing”, A Martin, N Calta, S Khairallah, J Wang, P DePond, A Fong, V Thampy, G Guss, A Kiss, KH Stone, CJ Tassone, J Weker, MF Toney, T van Buuren, M Matthews, Nature Comms, in press.X Gu, L Shaw, K Gu, MF Toney, Z Bao, Nature Comms 9, 534 (2018).B-R Chen, W Sun, D.A. Kitchaev, J.S. Mangum, V. Thampy, L.M. Garten, D.S. Ginley, B.P. Gorman, K.H. Stone, G. Ceder, M.F. Toney, LT Schelhas, Nature Comms 9, 2553 (2018).