Development of New B2 Type Shape Memory Alloys end theirs Application for Multi-functional Devices.

新型B2型形状记忆合金的开发结束了其在多功能器件中的应用。

基本信息

批准号：
13555181
负责人：
KAINUMA Ryosuke
金额：
$ 8.83万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2002
项目状态：
已结题

项目摘要

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.

形状记忆（SM）材料具有热传感器和执行器双重功能，是典型的智能材料之一，虽然形状记忆器件比铁电器件产生更大的功率和位移，但它们存在一个非常严重的问题，即对输入的响应。信号太慢，因为 SM 器件中的热导率是一个速率决定过程。最近，在 Ni-Mn-Ga 系统中开发出了可以通过磁场操作的铁磁形状记忆 (FSM) 合金。本研究对新型FSMA、具有B2 bcc有序结构的Co-Ni-Al合金进行了研究。本工作获得的具体结果如下：（1）转变温度：马氏体转变温度（Ms）和通过 DSC 和 VSM 测量确定了一些合金的居里温度 (Tc)，该结果表明 Co-Ni-Al 合金是有前景的候选材料。 FSMA。(2)晶体结构：母相和马氏体相分别具有B2和Ll_0结构，Ll_0相的c/a比为0.81。(3)形状记忆和机械性能：与γ相共存提高了延展性。通过训练处理可以获得合金的良好性能和完美的SM。（4）磁性能：使用单晶测定奥氏体和马氏体相的磁各向异性， (5)FSM线材，通过传统的轧制和拉拔技术可以生产0.5～1.0mmf的FSM线材，所得线材表现出伪弹性行为。