| Project/Area Number |
13555181
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 展開研究 |
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| Research Field |
Structural/Functional materials
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| Research Institution | TOHOKU UNIVERSITY |
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Principal Investigator |
KAINUMA Ryosuke Graduate School of Engineering, Associate Professor, 大学院・工学研究科, 助教授 (20202004)
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| Co-Investigator(Kenkyū-buntansha) |
OIKAWA Katsunri National Institute of Advanced Industrial Science and Technology, Tohoku Center, Senior Researcher, 東北センター, 主任研究員
OHNUMA Ikuo Graduate School of Engineering, Research Associate, 大学院・工学研究科, 助手 (20250714)
ISHIDA Kiyohito New Industry Creation Hatchery Center, Professor, 未来科学技術共同研究センター, 教授 (20151368)
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| Project Period (FY) |
2001 – 2002
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| Project Status |
Completed (Fiscal Year 2002)
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| Budget Amount *help |
¥13,800,000 (Direct Cost: ¥13,800,000)
Fiscal Year 2002: ¥5,400,000 (Direct Cost: ¥5,400,000)
Fiscal Year 2001: ¥8,400,000 (Direct Cost: ¥8,400,000)
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| Keywords | Martensitic Transformation / Magnetic Transition / Ferromagnetic Shape Memory / Co-Ni-Al base / Sensor / Smart Materials / 規磁気変態 / 強磁性形状記憶材料 |
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| Research Abstract |
Shape memory (SM) material which possesses double functions of thermo-sensor and actuator is one of the typical smart materials. Although the SM devices yield larger power and displacement than the ferroelectric one, they have a very serious problem in which the response for input signal is too slow, because the thermal conductivity in the SM devices is a rate determining process. Recently, ferromagnetic Shape memory (FSM) alloys that can be operated by magnetic field have been developed in the Ni-Mn-Ga system. In the present study, new type of FSMAs, Co-Ni-Al alloys with B2 bcc ordered structure were investigated.. The details of results obtained by the present work are as follows:
(1) Transformation temperatures: Martensitic transformation temperature (Ms) and Curie temperature (Tc) were determined by DSC and VSM measurement. Some alloys have Ms and To in relatively high temperatures region over room temperature. This result means that the Co-Ni-Al alloys can be a candidate of the promising FSMA.
(2) Crystal structure: The parent and martensits phases have B2 and Ll_0 structures, respectively. The c/a ration of the Ll_0, phase is 0.81.
(3) Shape memory and mechanical properties: Coexistence with γ phase improves the ductility of alloys and a perfect SM can be obtained by a training treatment.
(4) Magnetic properties: Magnetic anisotropies of austenite and martensite phases were determined using single crystals, and magnetostriction of about 0.3% was detected.
(5) FSM wire, FSM wire with 0.5 to 1.0mmf could be produced by conventional techniques of rolling and drawing. The obtained wire showed a pseudoelastic behavior.
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