PNNL

Dr. Choi is currently Task Leading/Principal investigating interconnects materials, coating materials and optimization and supporting sealing, and electrochemical processes for Solid Oxide Fuel Cell Stack Testing for DOE projects (SECA Core) at the Lab. He also joined structure materials and manufacturing projects. He is expert of metal solidification and manufacturing. (B.S, M.S. and Ph.D work) The experience in this area is over 16 years. Therefore, He has high potentials to expanding these solidification related working area. He was one of the manufacturing counselor and co-workers with HYUNDAI Motors and POSCO. In addition, His M.S. and Ph.D. work was related on Electromagnetic Processing and computer modeling. He had many international collaboration with JAPAN. He got Inventor recognition, Key Contributor and Outstanding Award in this PNNL. More than 120 publications, including journal articles, conference, reports, book chapters, and lectures.

• Ceramic Process (coating, electrochemical process, and Fuel Cells)
• Solidification and manufacturing Process (New advanced materials)
• Electromagnetic process for Materials and Energy production.
• Numerical Analysis

• Ph.D. Materials Science, Hanyang University, (South KOREA)
• M.S. Materials Science, Hanyang University
• B.S. Metallurgy Science and Engineering, Hanyang University

• American Ceramic Society (ACerS)
• The Minerals, Metals, and Materials Society (TMS)
• The Korean Institute of Metals and Materials
• The Korean Foundrymen’s Society
• The Japan Institute of Light Metals

• U.S. Patent No. 10,577,694, March 3, 2020, "PROTECTIVE ALUMINUM OXIDE SURFACE COATINGS AND LOW-TEMPERATURE FORMING PROCESS FOR HIGH-TEMPERATURE APPLICATIONS ".
• U.S. Patent No. 10,378,094, August 13, 2019, "Reactive Coating Processes".
• U.S. Patent No. 9,481,923, November 1, 2016, "Methods for both coating a substrate with aluminum oxide and infusing the substrate with elemental aluminum".
• U.S. Patent No. 9,418,779, August 16, 2016, "PROCESS FOR PREPARING SCALABLE QUANTITIES OF HIGH PURITY MANGANESE BISMUTH MAGNETIC MATERIALS FOR FABRICATION OF PERMANENT MAGNETS ( (iEdison No. 0685901-12-0012))".
• U.S. Patent No. 7,691,488, April 6, 2010, "Diffusion Barriers in Modified Air Brazes".

2025

• Pole M., S. Mukhopadhyay, S. Kastamo, A. Loukus, J. Choi, M.J. Olszta, and D.R. Herling, et al. 2025. "Tribological Behavior of Hybrid Aluminum-TiB2 Metal Matrix Composites for Brake Rotor Applications." Wear 562-563, no. _:Art No. 205639. PNNL-SA-197794. doi:10.1016/j.wear.2024.205639

2024

• Byun T., D. Collins, T.G. Lach, J. Choi, and S.A. Maloy. 2024. "Thermomechanical Processing for Improved Mechanical Properties of HT9 Steels." Materials 17, no. 15:Art. No. 3805. PNNL-SA-202545. doi:10.3390/ma17153803

2023

• Reddy M.J., B. Kamecki, B. Talic, E. Zanchi, F. Smeacetto, J.S. Hardy, and J. Choi, et al. 2023. "Experimental review of the performances of protective coatings for interconnects in solid oxide fuel cells." Journal of Power Sources 568. PNNL-SA-182133. doi:10.1016/j.jpowsour.2023.232831

2022

• Hardy J.S., Y. Chou, J. Choi, and J. Li. 2022. Aluminization Coatings and Glass Seals for High Temperature Systems - CRADA 536 (Final Report). PNNL-33817. Richland, WA: Pacific Northwest National Laboratory. Aluminization Coatings and Glass Seals for High Temperature Systems - CRADA 536 (Final Report)

2021

• Choi J., J.F. Bonnett, N.L. Canfield, and J.S. Hardy. 2021. "Electrically Conductive and Protective Coating Compatibility with LSCF Cathodes." In Proceedings of the 17th International Symposium on Solid Oxide Fuel Cells, (SOFC 2021), July 18-23, 2021, Stockholm, Sweden. ECS Transactions, 103, 1827-1834. PNNL-SA-162493. doi:10.1149/10301.1827ecst
• Chou Y., T. Jin, N.L. Canfield, J.F. Bonnett, J. Choi, and J.S. Hardy. 2021. "Lanthanum Strontium Cobaltite-Alumina Fiber Composite Contact Material for Solid Oxide Fuel Cells." In Proceedings of the 17th International Symposium on Solid Oxide Fuel Cells (SOFC-XVII), July 18-23, 2021, Stockholm, Sweden. ECS Transactions, 103, 1835 - 1846. PNNL-SA-162624. doi:10.1149/10301.1835ecst

2020

• Rashidi S., J. Choi, J.W. Stevenson, A. Pandey, and R.K. Gupta. 2020. "High Temperature Oxidation Behavior of Aluminized Haynes 230." Corrosion Science 174. PNNL-SA-153949. doi:10.1016/j.corsci.2020.108835

2019

• Byun T., D.A. Collins, T.G. Lach, J. Choi, and E.L. Barkley. 2019. Fracture Toughness of High-Cr Steels after Various Thermomechanical Treatments. PNNL-29076. Richland, WA: Pacific Northwest National Laboratory. Fracture Toughness of High-Cr Steels after Various Thermomechanical Treatments
• Rashidi S., J. Choi, J.W. Stevenson, A. Pandey, and R.K. Gupta. 2019. "Effect of Aluminizing on the High Temperature Oxidation Behavior of an Alumina Forming Austenitic Stainless Steel." JOM. The Journal of the Minerals, Metals and Materials Society 71, no. 1:109-115. PNNL-SA-138140. doi:10.1007/s11837-018-3155-y
• Wang R., Z. Sun, J. Choi, S.N. Basu, J.W. Stevenson, and M.C. Tucker. 2019. "Ferritic stainless steel interconnects for protonic ceramic electrochemical cell stacks: Oxidation behavior and protective coatings." International Journal of Hydrogen Energy 44, no. 47:25297-25309. PNNL-SA-149461. doi:10.1016/j.ijhydene.2019.08.041

2018

• Stevenson J.W., and J. Choi. 2018. Development of Protective Coatings for 1 kW Hot Zone - CRADA 376 (Final Report). PNNL-27906. Richland, WA: Pacific Northwest National Laboratory. doi:10.2172/1474214.

2017

• Choi J., and J.W. Stevenson. 2017. "Electrically Conductive and Protective Coating for Planar SOFC Stacks." In ECS Transactions, 78, 1633-1640. Pennington, New Jersey:Electrochemical Society. PNNL-SA-125322. doi:10.1149/07801.1633ecst
• Chou Y., J. Choi, J.W. Stevenson, C. Liang, B. Hu, W. Rodriguez, and A. Aphale, et al. 2017. "Performance and Microstructure of a Novel Cr-Getter Material with LSCF-based Cells in a Generic Stack Test Fixture." In ECS Transactions, 78, 1047-1054. Pennington, New Jersey:Electrochemical Society. PNNL-SA-131556. doi:10.1149/07801.1047ecst

2016

• Jiang X., T.J. Roosendaal, X. Lu, O. Palasyuk, K.W. Dennis, M.E. Dahl, and J. Choi, et al. 2016. "Mechanical and Electrical Properties of Low Temperature Phase MnBi." Journal of Applied Physics 119, no. 3:Article No. 033903. PNNL-SA-111396. doi:10.1063/1.4939811
• Overman N.R., S. Mathaudhu, J. Choi, T.J. Roosendaal, and S.G. Pitman. 2016. "Microstructure and Mechanical Properties of a Novel Rapidly Solidified, High-Temperature Al-Alloy." Materials Characterization 112. PNNL-SA-112327. doi:10.1016/j.matchar.2015.12.015
• Prabhakaran R., J. Choi, E.V. Stephens, D. Catalini, C.A. Lavender, and A. Rohatgi. 2016. "Mechanical Characterization and Corrosion Testing of X608 Al Alloy." In Light Metals 2016, edited by E. Williams. 145-150. Hoboken, New Jersey:John Wiley & Sons, Inc. PNNL-SA-113866.
• Xie W., E. Polikarpov, J. Choi, M.E. Bowden, K. Sun, and J. Cui. 2016. "Effect of ball milling and heat treatment process on MnBi powders magnetic properties." Journal of Alloys and Compounds 680. PNNL-SA-119027. doi:10.1016/j.jallcom.2016.04.097

2015

• Choi J., A. Rohatgi, M.T. Smith, and C.A. Lavender. 2015. "Process Development for Stamping �-Pillar Covers with Aluminum." In Light Metals 2015: Proceedings of the symposia sponsored by the TMS Aluminum Committee at the TMS 2015 Annual Meeting & Exhibition, March 15-19, 2015, Orlando, Florida, edited by M Hyland, 197-202. Hoboken, New Jersey:John Wiley and Sons, Inc. PNNL-SA-105374. doi:10.1002/9781119093435.ch35

2014

• Chou Y.S., J.W. Stevenson, and J. Choi. 2014. "Long-term evaluation of solid oxide fuel cell candidate materials in a 3-cell generic short stack fixture, Part II: sealing glass stability, microstructure and interfacial reactions." Journal of Power Sources 250. PNNL-SA-101236. doi:10.1016/j.jpowsour.2013.09.148
• Cui J., J. Choi, E. Polikarpov, M.E. Bowden, W. Xie, G. Li, and Z. Nie, et al. 2014. "Effect of Composition and Heat Treatment on MnBi Magnetic Materials." Acta Materialia 79. PNNL-SA-102205. doi:10.1016/j.actamat.2014.07.034
• Cui J., J. Choi, G. Li, E. Polikarpov, J.T. Darsell, M.J. Kramer, and N. Zarkevich, et al. 2014. "Development of MnBi permanent magnet: neutron diffraction of MnBi powder." Journal of Applied Physics 115, no. 17:Article No. 17A743. PNNL-SA-98434. doi:10.1063/1.4867230
• Cui J., J. Choi, G. Li, E. Polikarpov, J.T. Darsell, N.R. Overman, and M.J. Olszta, et al. 2014. "Thermal Stability of MnBi Magnetic Materials." Journal of Physics: Condensed Matter 26, no. 6:Article No. 064212. PNNL-SA-97263. doi:10.1088/0953-8984/26/6/064212

2013

• Chou Y.S., J.W. Stevenson, and J. Choi. 2013. "Evaluation of a single cell and candidate materials with high water content hydrogen in a generic solid oxide fuel cell stack test fixture, Part II: materials and interface characterization." International Journal of Applied Ceramic Technology 10, no. 1:97-106. PNNL-SA-82494. doi:10.1111/j.1744-7402.2012.02753.x
• Joshi V.V., J. Choi, J.T. Darsell, A. Meier, and K.S. Weil. 2013. "Reactive Air Aluminizing of Nicrofer-6025HT for Use in Advanced Coal-Based Power Plants." Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science 44, no. 1 (Supplement):188-192. PNNL-SA-87186. doi:10.1007/s11661-012-1237-y

2012

• Chou Y.S., E.C. Thomsen, J. Choi, and J.W. Stevenson. 2012. "Compliant alkali silicate sealing glass for solid oxide fuel cell applications: Combined stability in isothermal ageing and thermal cycling with YSZ coated ferritic stainless steels." Journal of Power Sources 197, no. 1:154-160. PNNL-SA-82493. doi:10.1016/j.jpowsour.2011.09.027
• Chou Y.S., E.C. Thomsen, J. Choi, and J.W. Stevenson. 2012. "Compliant alkali silicate sealing glass for solid oxide fuel cell applications: the effect of protective YSZ coating on electrical stability in dual environment." Journal of Power Sources 202. PNNL-SA-84397. doi:10.1016/j.jpowsour.2011.11.017
• Chou Y.S., J. Choi, and J.W. Stevenson. 2012. "Compliant alkali silicate sealing glass for solid oxide fuel cell applications: the effect of protective alumina coating on electrical stability in dual environment." International Journal of Hydrogen Energy 37, no. 23:18372-18380. PNNL-SA-90858. doi:10.1016/j.ijhydene.2012.08.084

2011

• Choi J., K.S. Weil, Y.S. Chou, J.W. Stevenson, and Z. Yang. 2011. "Development of MnCoO Coating with New Aluminizing Process for Planar SOFC Stacks." International Journal of Hydrogen Energy 36, no. 7:4549-4556. PNNL-SA-67464. doi:10.1016/j.ijhydene.2010.04.110
• Chou Y.S., E.C. Thomsen, J. Choi, W.E. Voldrich, J.W. Templeton, and J.W. Stevenson. 2011. "Development and Implementation of Stack Fixture Tests." In 2011 Office of Fossil Energy Fuel Cell Program Annual Report. 163-167. Washington, District Of Columbia:Department of Energy. PNNL-SA-80675.
• Chou Y.S., E.C. Thomsen, R.T. Williams, J. Choi, N.L. Canfield, J.F. Bonnett, and J.W. Stevenson, et al. 2011. "Compliant alkali silicate sealing glass for solid oxide fuel cell applications: thermal cycle stability and chemical compatibility." Journal of Power Sources 196, no. 5:2709-2716. PNNL-SA-76697. doi:10.1016/j.jpowsour.2010.11.020
• Xia G., R.C. Scott, X.S. Li, Z. Nie, J. Choi, and J.W. Stevenson. 2011. "Development of SOFC Interconnects and Coatings." In 2011 Office of Fossil Energy Fuel Cell Program Annual Report. 120-123. Washington, District Of Columbia:Department of Energy. PNNL-SA-80405.

2010

• Hong S., K.S. Weil, J. Choi, I. Bae, and J. Pan. 2010. "Annealing induced interfacial layers in niobium-clad stainless steel developed as a bipolar plate material for polymer electrolyte membrane fuel cell stacks." Journal of Power Sources 195, no. 9:2592 - 2598. PNNL-SA-62847. doi:10.1016/j.jpowsour.2009.10.034

2009

• Choi J., K.S. Weil, and J.W. Stevenson. 2009. "Optimization of Protective Coatings for SOFC Interconnects." In Office of Fossil Energy Fuel Cell Program FY 2009 Annual Report. Washington, Dc:Office of Fossil Energy Fuel Cell Program. PNNL-18469.

2008

• Kim J.Y., J. Choi, and K.S. Weil. 2008. "Mechanical properties and dual atmosphere tolerance of Ag-Al based braze." International Journal of Hydrogen Energy 33, no. 14:3952-3961. PNNL-SA-55673.
• Kim J.Y., M.H. Engelhard, J. Choi, and K.S. Weil. 2008. "Effects of atmospheres on bonding characteristics of silver and alumina." International Journal of Hydrogen Energy 33, no. 14:4001-4011. PNNL-SA-55674. doi:10.1016/j.ijhydene.2007.12.042