The 208th MANA & 91st ICYS Joint Seminar
Dr. Qingsong Mei & Dr. Ken Watanabe
| Date | June 3, Friday |
| Time | 15:30-16:30 |
| Place | 8F, Room #811, Central Bldg., SENGEN, NIMS |
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15:30-16:00
On the deformation-induced reverse martensitic transformation in NiTi alloy
Mechanical deformation has been known to have significant effect on the phase transformation and mechanical properties of NiTi alloy, e.g., the stress-induced martensitic transformation and martensite stabilization. Under severe plastic deformation conditions, new interesting phase transformation behavior may occur. In this study we reported the deformation-induced reverse martensitic transformation (DRMT) in NiTi. We showed that DRMT in NiTi can be observed by various deformations methods and was enhanced by increase of strain or strain rate. To reveal the mechanism of DRMT, the phase transformation behavior of samples with different strain levels was studied by differential scanning calorimeter (DSC), showing an evident effect of strain on transformation temperature and enthalpy. Microstructure observations showed that B2 nanograins were formed at regions with high strain concentrations. Possible mechanism for DRMT was discussed considering the kinetics and thermodynamics of the reverse transformation.
Speaker
Dr. Qingsong Mei, ICYS-Sengen Researcher, NIMS
Chair
Dr. Koichi Tsuchiya, ICYS Deputy Director, NIMS
16:00-16:30
Oxygen permeation through mixed ionic-electronic conductive membranes
Mixed ionic-electronic conductors are materials which conduct both oxide ions and electronic charge carriers (electron and/or hole) simultaneously. Therefore, those materials have been paid much attention as electrochemical devices for energy and environmental fields such as an electrode of SOFC, a gas sensor, an oxygen permeable membrane, membrane reactors for synthesis gases and so on. In this talk, I will discuss the possibility of membrane reactors for CO2 capture and storage, and the development of high efficient oxygen permeable membranes based on perovskite-type oxides will be discussed.
Speaker
Dr. Ken Watanabes, ICYS-MANA Researcher, NIMS
Chair
Dr. Kazunori Takada, MANA PI, MANA, NIMS