Recent results of the reduced activation ferritic/martensitic steel development S. Jitsukawa a, * , A. Kimura b , A. Kohyama b , R.L. Klueh c , A.A. Tavassoli d , B. van der Schaaf e , G.R. Odette f , J.W. Rensman e , M. Victoria g , C. Petersen h a Radiation Effects and Analysis, Department of Materials Science, Japan Atomic Energy Research Institute, 2-4 Shirakata, Tokai-Mura, Ibaraki-Ken 319-1195, Japan b IAE, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan c ORNL, Oak Ridge, TN 37831, USA d CEA/Saclay, 9119 Gif sur Yvette cedex, France e NRG, P.O. Box 25, Petten, The Netherlands f UCSB, CA 93106-5070, USA g PSI, Villigen, Switzerland h FZK-IMF, Postfach 3640, Karlsruhe, Germany Abstract Significant progress has been achieved in the international research effort on reduced-activation steels. Extensive tensile, fracture toughness, fatigue, and creep properties in unirradiated and irradiated conditions have been performed and evaluated. Since it is not possible to include all work in this limited review, selected areas will be presented to indicate the scope and progress of recent international efforts. These include (1) results from mechanical properties studies that have been combined in databases to determine materials design limits for the preliminary design of an ITER blanket module. (2) Results indicate that the effect of transmutation-produced helium on fracture toughness is smaller than indicated previously. (3) Further efforts to reduce irradiation-induced degradation of fracture toughness. (4) The introduction of a post-irradiation constitutive equation for plastic deformation. (5) The production of ODS steels that have been used to improve high-temperature strength. (6) The method developed to improve fracture toughness of ODS steels. Ó 2004 Published by Elsevier B.V. 1. Introduction Since the last International Conference on Fusion Reactor Materials (ICFRM-10), considerable progress has been made in the continuing development of the reduced-activation ferritic/martensitic steels (RAF/Ms) for fusion applications. The objective of this paper is to review progress since ICFRM-10, but because of the extensive international effort involved and the limited space available for this presentation, it will only be possible to highlight a small amount of the work. The subject areas chosen for this review were to provide an indication of the scope of the work being performed and the progress that has been made. Evidence of this pro- gress is further shown by the wide range subjects covered in the papers published in this proceedings. 2. International collaborations International collaborations, such as those under the framework of the International Energy Agency * Corresponding author. Tel.: +81-29 282 5391; fax: +81-29 282 5922. E-mail address: jitsukawa@ifmif.tokai.jaeri.go.jp (S. Jitsuk- awa). 0022-3115/$ - see front matter Ó 2004 Published by Elsevier B.V. doi:10.1016/j.jnucmat.2004.04.319 www.elsevier.com/locate/jnucmat Journal of Nuclear Materials 329–333 (2004) 39–46