2003 Fiscal Year Final Research Report Summary
Development of resonant ultrasound spectroscopy and its application to superionic conductors
Grant-in-Aid for Scientific Research (C)
|Allocation Type||Single-year Grants |
|Research Institution||The University of Tokushima |
KANASHIRO Tatsuo The University of Tokushima, Fac.of Engineering, Dept..Applied Physics and Mathematics, Professor (50035606)
MICHIHIRO Yoshitaka 徳島大学, Fac.of Engineering, Dept..Applied Physics and mathematics, Associate professor (00174061)
NAKAMURA Koichi 徳島大学, Fac.of Engineering, Dept..Applied Physics and mathematics, Lecturer (20284317)
|Project Period (FY)
2002 – 2003
|Keywords||superionic conductor / alkali halide / silver halide / resonant ultrasound spectroscopy / RUS / battery material / elastic constant / internal friction|
In the term of the project, the research results were obtained as follows.
1. Making the assemblies of sensor for high and low temperature measurements.
To measure the temperature dependence of the resonant ultrasound spectra (RUS) of crystals, the sensor assemblies were made by using buffer plates of glass ceramics for the ultrasound propagation. The assembly for high temperature (300K-800K) worked well, and the fine spectra were obtained in several crystals. The low temperature assembly (80K-300K) was now being tested.
2. Making the sphere shaping tool and the position controle unit.
The tool for sphere shaping of samples was prepared. The good sphere crystals of alkali halides were obtained by using this tool. Optionally, the position control unit was made to set the sample between the buffer plates of sensor assembly.
3. Measurements of RUS spectra and determination of the elastic constants.
Measurements were done for several crystals of alkali and silver halides with sphere, rectangular parallelpiped, and cylindrical shapes. The elastic constants of each crystal could be determined in good accuracy. By using the data, the deviation from the Cauchy relation (C12=C44) was estimated and compared with a model calculation of the multipole polarization due to the local density approximation (LDA) to discuss about the ease of the ionic diffusion. In addition, Gruneisen parameters were derived from the elastic constants and the ionic conduction was discussed by comparing the values of AgBr and NaCl.
4. Computatinal program far sphere samples.
To determine the elastic constants for sphere samples from the measured RUS spectra, a computational program was completed by getting the co-operation of Institute for Study of the Earth's Interior, Okayama University.
Research Products (8 results)