The susceptibility to hydrogen embrittlement increases with increasing strength of steel materials. The main research objective of my study is to elucidate the effectiveness of precipitate composition and size on hydrogen trapping ability of high strength steel materials. The experimental approach combines various mechanical tests with microscopy, hydrogen permeation test and hydrogen visualization, which will then be fed into simulations.
3rd the Monodzukuri Nippon Grand Award (2009)
31st the Technical Development Prize of the Japan Institute of Metals (2008)
28th the Technical Development Prize of the Japan Institute of Metals (2005)
1. A.Nagao, K.Hayashi, K.Oi, T.Ito and K.Hirata: Development of ultra high strength steel plates 'JFE-HYD960LE' and 'JFE-HYD1100LE' with excellent toughness and high resistance to delayed fracture for construction and industrial machinery use, Materia Japan, 47(2008), 93.
2. A.Nagao, K.Hayashi, K.Oi, S.Mitao and N.Shikanai: Refinement of cementite in high strength steel plates by rapid heating and tempering, Materials Science Forum, 539-543(2007), 4720.
3. A.Nagao, K.Oi, S.Mitao, Y.Kajita and M.Sugioka: Development of high strength steel plates with excellent toughness by controlling morphology of carbides through HOP (Heat-treatment On-line Process), Materia Japan, 44(2005), 148.
4. A.Nagao, S.Kuramoto, K.Ichitani and M.Kanno: Visualization of hydrogen transport in high strength steels affected by stress fields and hydrogen trapping, Scripta Materialia, 45(2001), 1227.
5. A.Nagao, S.Kuramoto, M.Kanno and T.Shiraga: Visualization of hydrogen diffusion promoted by stress gradient and plastic deformation in steels, Tetsu-to-Hagané 86(2000), 24.
6. A.Nagao, S.Kuramoto and M.Kanno: Detection and visualization of hydrogen in aluminum, Journal of Japan Institute of Light Metals, 49(1999), 89.
2009-present: Visiting Researcher, Department of Mechanical Science and Engineering & Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign
2004-2009: Senior Researcher, Plate & Shapes Research Department, Steel Research Laboratory, JFE Steel Corporation
2002-2004: Researcher, Plate & Shapes Research Department, Steel Research Laboratory, JFE Steel Corporation
PhD in Materials Engineering, The University of Tokyo, Japan (2002)
Thesis: Study on Delayed Fracture of Steel by Visualization of Hydrogen
MS in Materials Engineering, The University of Tokyo, Japan (1999)
BS in Materials Engineering, The University of Tokyo, Japan (1997)
Effects of precipitates on hydrogen embrittlement of high strength steel
Technique to visualize hydrogen in metals, which primarily uses hydrogen microprint technique
Visualization of hydrogen transport by dislocation in aluminum and steel
Visualization of hydrogen diffusion promoted by stress gradient and plastic deformation in steel
Visualization of hydrogen concentration at the stress-concentrated region of steel
Improvements of toughness and hydrogen embrittlement resistance of bainitic steel and martensitic steel by refinement of cementite through rapid heating and tempering