| Project/Area Number |
63460192
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
Physical properties of metals
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| Research Institution | Nara Women's University |
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Principal Investigator |
MATSUO Yoshie Nara Women's University Physics, associate professor, 理学部, 助教授 (00031675)
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| Project Period (FY) |
1988 – 1989
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| Project Status |
Completed (Fiscal Year 1989)
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| Budget Amount *help |
¥8,100,000 (Direct Cost: ¥8,100,000)
Fiscal Year 1989: ¥1,300,000 (Direct Cost: ¥1,300,000)
Fiscal Year 1988: ¥6,800,000 (Direct Cost: ¥6,800,000)
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| Keywords | Ag-Cd alloy / Martensitic transformation / X-ray diffuse scattering / Preceding phenomena |
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| Research Abstract |
X-ray diffuse scattering measurements have been carried out on beta -phase Ag-Cd alloys. Two instruments were used to measure the X-ray diffuse scattering intensity. One was a Rigaku AFC-5 four-circle diffractometer combined with a conventional X-ray generator at Nara Women's University. Another was Huber 5020.4 four-circle diffractometer installed at BL-4C at the Photon Factory of the National Laboratory for High Energy Physics.
Following notable features were found in the distributions of diffuse scattering intensity; (1) diffuse streaks running through the fundamental reflection points in the [11^^-0] directions, diffuse sheets extending uniformly parallel to the (111) planes, (3) diffuse peaks near q=(1/2)[11^^-0] positions along the [11^^-0] axis.
Furthermore, the intensity near q=(1/2)[11^^-0]-peak increases drastically at about 175K with decreasing temperature. On the other hand, the intensity of the [11^^-0]-streak decreases at this temperature.
As already reported for some kinds of beta phase alloys, anomalous diffuse scattering (1) and (2) are due to an inherent instability of the beta-phase. beta Ag-Cd alloy transforms into the M2H mertensite at low temperature. Thus, the diffuse peaks near q=(1/2)[110] position are considered to be due to a lattice modulation wave which causes the martensitic transition with the M2H structure.
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