Magnetic transformations during mechanical loading of magnetocaloric materials based on Heusler alloys

基于 Heusler 合金的磁热材料机械加载过程中的磁转变

• 批准号: 234141871
• 负责人: Professor Dr.-Ing. Hans Jürgen Maier
• 金额: --
• 依托单位: Institut für Werkstoffkunde (IW)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2015-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/234141871?language=en
• 关键词: Magnetic; transformations; during; mechanical; loading

Magnetic refrigeration based on the magnetocaloric effect is of a great interest due to its potential impact on energy saving. So far, this technology has only been employed for niche applications due to material limitations. Over the last decade, however, new alloys have been developed that demonstrate a large magnetocaloric effect and do not rely on rare earth elements. A promising new candidate material is Ni45Co5Mn36.7In13.3, where the martensitic transformation temperature shows a large temperature dependence on magnetic field of about 4 K/T. Moreover, the phase transformation can also be tuned by a superimposed mechanical stress as this material shows pseudoelasticity. Thus, the phase transformation and the associated heat release and absorption can be controlled in such a material by both applied stress and magnetic field. It is well known, however, that repeated cyclic loading can drastically affect the microstructure of a pseudoelastic material, which in turn leads to functional degradation.Thus, the objectives of the proposed research are two-fold. Firstly, the group at the Institute of Magnetism in Kyiv will focus on improving the NiCoMnIn system, to obtain a sufficiently large magnetocaloric effect in magnetic fields that are low enough with respect to actual applications. The alloys developed in Kyiv will be cyclically loaded within the current project in order to understand the microstructural mechanisms that lead to functional degradation. This part of the research will involve both cyclic mechanical loading and detailed microstructural characterization using electron microscopy. As measures of functional degradation both the changes in cyclic stress-strain response and magnetic permeability will be monitored.The result of the proposed research will allow for using both magnetic fields and superimposed stresses to widen the temperature range of magnetic refrigeration. At the same time understanding of the mechanisms that govern microstructural evolution will help to design new materials that demonstrate reduced functional degradation for the next generation of magnetic refrigeration systems.

基于磁化效应的磁制冷由于其对节能的潜在影响而引起了极大的兴趣。到目前为止，由于物质限制，该技术仅用于利基应用。然而，在过去的十年中，已经开发出了新的合金，这些合金表现出很大的磁性作用，并且不依赖稀土元素。有希望的新候选材料是NI45CO5MN36.7IN13.3，其中Martensisitic转换温度显示出对磁场约4 k/t的温度依赖性很大。此外，由于该材料显示伪弹性，因此相变的相变。因此，可以通过施加的应力和磁场在这种材料中控制相变的热量释放和吸收。然而，众所周知，重复的循环载荷会严重影响假弹性材料的微观结构，这又导致功能性降解。首先，基辅磁性研究所的小组将重点放在改善尼科诺尼蛋白系统上，以在磁场中获得足够大的磁联性效应，而相对于实际应用，该磁场足够低。基辅合金将在当前项目中周期性加载，以了解导致功能降解的微结构机制。研究的这一部分将涉及使用电子显微镜的循环机械载荷和详细的显微结构表征。作为功​​能降解的度量，将监测环状应力应变响应和磁渗透性的变化。拟议的研究的结果将允许同时使用磁场和叠加应力来扩大磁制冷的温度范围。同时，了解控制微观结构演化的机制将有助于设计新材料，以证明下一代磁制冷系统的功能降解降低。

项目成果

Stress-induced resistivity changes in a Ni-Mn-In alloy

• DOI: 10.1063/1.4917016
• 发表时间: 2015-04
• 期刊: Applied Physics Letters
• 影响因子: 4
• 作者: V. Kokorin;S. Konoplyuk;A. Dalinger;S. E. Thürer;G. Gerstein;H. Maier

Effect of thermal cycling on the martensitic transformation in Ni-Mn-In alloys

• DOI: 10.1063/1.4895585
• 发表时间: 2014-09
• 期刊: Journal of Applied Physics
• 影响因子: 3.2
• 作者: V. Kokorin;V. Koledov;V. Shavrov;S. Konoplyuk;S. E. Thürer;D. A. Troyanovsky;H. Maier;V. Khovaylo

Stress-induced transformation in a Ni-Mn-In alloy and the concomitant change of resistivity

Ni-Mn-In 合金中的应力诱导转变以及随之而来的电阻率变化

• DOI: 10.1051/matecconf/20153305007
• 发表时间: 2015
• 作者: Kokorin;Konoplyuk;Dalinger;Thürer;Gerstein;Mashirov;Stetskiv
• 通讯作者: Stetskiv