Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
measurement and analysis techniques in X-ray photoelectron spectroscopy; From NAP-HARPES to 4D-XPSToyoda, Satoshi*; Yamamoto, Tomoki*; Yoshimura, Masashi*; Sumida, Hirosuke*; Mineoi, Susumu*; Machida, Masatake*; Yoshigoe, Akitaka; Suzuki, Satoru*; Yokoyama, Kazushi*; Ohashi, Yuji*; et al.
Vacuum and Surface Science, 64(2), p.86 - 91, 2021/02
We have developed measurement and analysis techniques in X-ray photoelectron spectroscopy. To begin with, time-division depth profiles of gate stacked film interfaces have been achieved by NAP-HARPES (Near Ambient Pressure Hard X-ray Angle-Resolved Photo Emission Spectroscopy) data. We then have promoted our methods to quickly perform peak fittings and depth profiling from time-division ARPES data, which enables us to realize 4D-XPS analysis. It is found that the traditional maximum entropy method (MEM) combined with Jackknife averaging of sparse modeling in NAP-HARPES data is effective to perform dynamic measurement of depth profiles with high precision.
Asano, Wataru*; Katsuyama, Jinya; Onizawa, Kunio; Mochizuki, Masahito*; Toyoda, Masao*
Proceedings of 2008 ASME Pressure Vessels and Piping Division Conference (PVP 2008) (CD-ROM), 8 Pages, 2008/07
Stress corrosion cracking near welding zone of core internals and/or recirculation pipes of Type 316L stainless steel are initiated and grown at inner surface due to tensile residual stress and hardening. Surface-machining is conducted before and after piping butt-welding to match the ID of pipes and to provide a smooth surface finish, respectively. In present work, simulation evaluated residual stress by surface-machining before welding by using full scale FEM analysis was compared with experimental measurements. Piping-butt welding simulation was conducted after the surface-machining to evaluate redistribution behavior of residual stress by welding. Estimation of Vickers hardness distribution by surface-machining was carried out based on strained region map observed by FE-SEM equipped with EBSD and compared with experimental measurements. The effect of surface-machining before/after welding on distribution of residual stress and hardening are presented.
Katsuyama, Jinya; Mochizuki, Masahito*; Mori, Hiroaki*; Asano, Wataru*; An, G. B.*; Toyoda, Masao*
Materials Science Forum, 580-582, p.573 - 576, 2008/00
Recently, stress corrosion cracking (SCC) of primary piping of stainless steel has been observed. SCC is considered to initiate and progress at near the welding zone in butt-welded pipes, because of the tensile residual stress introduced by welding. In present work, three-dimensional and axisymmetric thermo-elastic-plastic finite element analyses have been carried out, in order to clarify the effect of geometrical and welding conditions on through-thickness residual stress. In particular, butt-welding joints of SUS316L pipes have been examined. The residual stress was simulated by three-dimensional and axisymmetric models and the results were compared and discussed in detail.
Mori, Hiroaki*; Katsuyama, Jinya; Mochizuki, Masahito*; Nishimoto, Kazutoshi*; Toyoda, Masao*
Zairyo To Kankyo, 56(12), p.568 - 575, 2007/12
no abstracts in English
Mori, Hiroaki*; Katsuyama, Jinya; Mochizuki, Masahito*; Nishimoto, Kazutoshi*; Toyoda, Masao*
Corrosion Engineering, 56(12), p.757 - 770, 2007/09
In order to clarify the effects of residual stress and hardening on intergranular stress corrosion cracking (IGSCC) behavior in the welds of Type 316L stainless steel with surface hardening, the residual stress and hardness in the butt joint of pipes were estimated and grain boundary sliding was analyzed from the viewpoint of microdeformation. The residual stress and hardness in hard-machined surfaces near welds was clarified from experiment and analysis method. Grain boundary sliding in the cold-rolled specimen occurs in smaller strain conditions than that in as-received specimen; the amount of grain boundary sliding increases remarkably with an increase in rolling reduction. We also clarified that grain boundary energy is raised by grain boundary sliding. On the basis of the results, we concluded that the cause of IGSCC in the welds of Type 316L stainless steel with surface hardening is the increase in grain boundary energy induced by residual stress of welding and surface hardening.
Katsuyama, Jinya; Asano, Wataru*; Onizawa, Kunio; Mochizuki, Masahito*; Toyoda, Masao*
Proceedings of 2007 ASME Pressure Vessels and Piping Division Conference/8th International Conference on Creep and Fatigue at Elevated Temperatures (PVP 2007/CREEP-8) (CD-ROM), 8 Pages, 2007/07
Stress corrosion cracking (SCC) of recirculation pipes of austenite stainless steel has been observed. The SCC initiates and grows near the welding zone because of high tensile residual stress by welding. Therefore, the residual stress analysis due to welds of piping is becoming important. In present work, the through-thickness residual stress distributions near multi-pass butt-welds of Type 316L pipes have been calculated by thermo-elastic-plastic analyses. Then crack growth simulations were performed using calculated residual stress distributions. The effects of geometric and welding conditions on crack growth behavior were also discussed.
Mochizuki, Masahito*; Higuchi, Ryota*; Katsuyama, Jinya; Toyoda, Masao*
Proceedings of 2007 ASME Pressure Vessels and Piping Division Conference/8th International Conference on Creep and Fatigue at Elevated Temperatures (PVP 2007/CREEP-8) (CD-ROM), 8 Pages, 2007/07
The strength properties of structural steels or their weld zone are influenced by the microscopic heterogeneity. It is important to investigate the stress distribution for clarification of the mechanism of fracture and the material design by considering a grain boundary or its neighborhood because either can be a zone where the stress concentration is likely to occur due to a mismatch of the displacement. For this purpose, FEM-MD coupling method is one of the useful methods because it can treat the mismatch of the displacement caused by the microscopic heterogeneity. In this study, FEM-MD coupling method is proposed and the influence of the microscopic heterogeneity of steels is investigated by using FEM-MD coupling method.
Katsuyama, Jinya; Mochizuki, Masahito*; An, G. B.*; Toyoda, Masao*
Proceedings of International Welding/Joining Conference-Korea 2007 (IWJC-Korea 2007), p.316 - 317, 2007/05
Recently, stress corrosion cracking (SCC) of primary piping of stainless steel has been observed. SCC is considered to initiate and progress at near the welding zone in butt-welded pipes, because of the tensile residual stress introduced by welding. In present work, three-dimensional and axisymmetric thermo-elastic-plastic finite element analyses have been carried out, in order to clarify the effect of geometrical and welding conditions on through-thickness residual stress. In particular, butt-welding joints of SUS316L pipes have been examined. The residual stress was simulated by three-dimensional and axisymmetric models and the results were compared and discussed in detail.
Mori, Hiroaki*; Katsuyama, Jinya; Mochizuki, Masahito*; Nishimoto, Kazutoshi*; Toyoda, Masao*
no journal, ,
no abstracts in English
