Microstructure evolution and yield strength of CLAM steel in low irradiation condition

Abstract The microstructure and yield strength of China low activation martensitic (CLAM) steel were observed and tested. The evolution of defects, including He bubbles and dislocation loops, and MC carbides were analyzed. According to the microstructure observation results, a two-step simulation model was established to analyze the relationship between microstructure and strength. For the first step, a rate theory model was used to simulate the evolution of defects (He bubbles and dislocation loops). The incubation, nucleation and growth stage of defects were shown by simulation results. For the second step, the simulation results of defect evolution were added into a superposition strengthening model, which combined different strengthening methods, to simulate the yield strength of CLAM steel in high temperature and irradiation condition. Based on both experimental and simulation results, the effect of high temperature and irradiation on microstructure and strength was discussed in CLAM steels. The simulation results of yield strength were basically consistent with experimental results.

[1]  Jijun Zhao,et al.  Tensile strain-induced softening of iron at high temperature , 2015, Scientific Reports.

[2]  U. F. Kocks,et al.  Kinetics of flow and strain-hardening☆ , 1981 .

[3]  Jian Wang,et al.  Peierls stress in face-centered-cubic metals predicted from an improved semi-discrete variation Peierls-Nabarro model , 2016 .

[4]  H. Duan,et al.  Dislocation-mediated strain hardening in tungsten: Thermo-mechanical plasticity theory and experimental validation , 2015 .

[5]  C. Zhang,et al.  Nanocrystallization of a quenched RAFM steel and microstructure evolution during annealing heat treatment , 2013 .

[6]  F. Luo,et al.  Rate theory modeling of dislocation loops in RAFM steel under helium ion irradiation and comparison with experiments , 2015 .

[7]  M. D. Mathew,et al.  Applicability of the one-internal-variable Kocks–Mecking approach for tensile flow and work hardening behaviour of modified 9Cr–1Mo steel , 2013 .

[8]  J. Roth,et al.  Erosion study of Fe–W binary mixed layer prepared as model system for RAFM steel , 2015 .

[9]  Zhenglian Liu,et al.  Effect of magnetic field on interfacial energy and precipitation behavior of carbides in reduced activation steels , 2011 .

[10]  Laurent Proville,et al.  Dislocation depinning from ordered nanophases in a model fcc crystal: From cutting mechanism to Orowan looping , 2010 .

[11]  M. Victoria,et al.  Microstructure assessment of the low activation ferritic/martensitic steel F82H , 1998 .

[12]  Ziya Wang,et al.  Evaluation of irradiation hardening and microstructure evolution under the synergistic interaction of He and subsequent Fe ions irradiation in CLAM steel , 2016 .

[13]  David N. Seidman,et al.  Prediction of the yield strength of a secondary-hardening steel , 2013 .

[14]  M. D. Mathew,et al.  Creep deformation and rupture behaviour of 9Cr–1W–0.2V–0.06Ta Reduced Activation Ferritic–Martensitic steel , 2012 .

[15]  M. Nastasi,et al.  Helium bubble growth at BCC twist grain boundaries , 2011 .

[16]  M. Monge,et al.  Texture and mechanical properties of EUROFER 97 steel processed by ECAP , 2011 .

[17]  M. Tonks,et al.  Phase-field simulations of gas density within bubbles in metals under irradiation , 2011 .

[19]  H.-C. Schneider,et al.  Tensile behavior of RAFM alloys after neutron irradiation of up to 16.3 dpa between 250 and 450 °C , 2014 .

[20]  J. Sietsma,et al.  A physically based yield criterion II. Incorporation of Hall Petch effect and resistance due to thermally activated dislocation glide , 2016 .

[21]  S. Msolli.  Thermoelastoviscoplastic modeling of RAFM steel JLF-1 using tensile and low cycle fatigue experiments , 2014 .

[22]  A. Kohyama,et al.  Helium effects on mechanical properties and microstructure of high fluence ion-irradiated RAFM steel , 2007 .

[23]  C. Zhang,et al.  Improving high temperature creep resistance of reduced activation steels by addition of nitrogen and intermediate heat treatment , 2014 .

[24]  C. Weinberger,et al.  A physically based model of temperature and strain rate dependent yield in BCC metals: Implementation into crystal plasticity , 2015 .

[25]  Farong Wan,et al.  Effects of carbide precipitate on the mechanical properties and irradiation behavior of the low activation martensitic steel , 2013 .

[26]  Hisashi Tanigawa,et al.  Helium effects on microstructural change in RAFM steel under irradiation: Reaction rate theory modeling , 2015 .

[27]  T. Yoshiie,et al.  Reaction kinetics analysis of damage evolution in accelerator driven system beam windows , 2008 .

[28]  J. Aktaa,et al.  Mechanical properties and TEM examination of RAFM steels irradiated up to 70 dpa in BOR-60 , 2011 .