Experimental studies of novel magnetic refrigerants by high field X-ray diffraction measurements

高场X射线衍射测量新型磁性制冷剂的实验研究

• 批准号: 17560610
• 负责人: KOYAMA Keiichi
• 金额: $ 2.12万
• 依托单位: Tohoku University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17560610/
• 关键词: high magnetic field; powder X-ray diffraction; crystal structure; magnetic refrigerant; lst-order phase transition; magnetocaloric effect; structural transformation; 高磁気熱量材料; 包晶反応; スピン再配列; X線回折装置; 磁気体積効果; 磁気冷凍; 低温; 高磁気熱材料; 高磁歪材料; 磁場誘起形状記憶強

In this work, I have studied novel magnetic refrigerants by high X-ray diffraction measurements. I have clarified some topics as follows:1. I observed a field-induced magnetic and structural transition on large magnetocaloric material MnFeP_0.5As_0.5. The material has a hexagonal structure and shows that the parameters a and c deform by 0.5% and 1.0%, respectively, by magnetic field.2. Large magnetocaloric material Gd_5(GeFe)Si_2 shows a structural transformation from a monoclinic structure to an orthorhombic structure by high magnetic field.3. I observed a field-induced reverse martensitic transformation from an orthorhombic structure to a cubic structure in large magnetocaloric material Ni_<50>Mn_<36>Sn_<14>.4. The ferromagnetic shape memory alloy Ni_<50>Mn_<36>Sn_<14> shows a large magnetoresistance effect accompanied by the field-induced reverse martensitic transformation.5. I revealed the magnetic and thermoelectric properties of magnetic shape memory alloy Ni_<50>Mn_<36>Sn_<14> in high magnetic fields.6. I observed a metamagnetic (1st-order) transition of MnBi at high temperature of 630 K by high magnetic fields.7. MnBi shows a large magnetocaloric effect at the 1st-order magnetic transition temperature. By applying high magnetic field, the 1st-order magnetic transition temperature of MnBi increases at the rate of 2 KT^<-1>.8. Magnetic field and pressure induced magnetic transitions were observed in DyB_2C_2 below 10 K.

在这项工作中，我通过高X射线衍射测量研究了新型的磁制冷剂。我已经阐明了一些主题，如下所示：1。我观察到大磁化材料MNFEP_0.5AS_0.5上的磁场诱导的磁和结构过渡。该材料具有六边形结构，并表明参数A和C分别通过磁场变形了0.5％和1.0％。2。大型磁化材料GD_5（GEFE）SI_2通过高磁场显示了从单斜结构到正交结构的结构转换。3。我观察到了一个场引起的反向马氏体转变，从正骨结构到大磁平原材料Ni_ <50> Mn_ <36> SN_ <14> .4中的立方结构。铁磁形状内存合金Ni_ <50> Mn_ <36> sn_ <14>显示出较大的磁势效应，并伴随着野外诱导的反向马氏体转换。5。我揭示了磁性记忆合金Ni_ <50> Mn_ <36> sn_ <14>在高磁场中的磁性和热电特性。6。我观察到高磁场在630 K的高温下MNBI的元磁（一阶）过渡。7。 MNBI在一阶磁过渡温度下显示出较大的磁化效应。通过施加高磁场，MNBI的一阶磁过渡温度以2 kt^<-1> .8的速率升高。在10 K以下的DYB_2C_2中观察到磁场和压力诱导的磁过渡。

项目成果

「研究成果報告書概要(和文)」より

摘自《研究结果报告摘要（日文）》

• 发表时间: 2005
• 作者: Kawauchi;et. al.;Nishimura et al.;Dezawa et al.;Yoshizawa et al.;星野 幹雄;星野 幹雄
• 通讯作者: 星野 幹雄

High Field X-ray diffraction measurements of novel ferromagnetic shape memory alloy Ni_50Mn_36Sn_14

新型铁磁形状记忆合金Ni_50Mn_36Sn_14的高场X射线衍射测量

• 发表时间: 2005
• 作者: K. Koyama;H. Okada;K. Watanabe;T. Kanomata;R. Kainuma;W. Ito;K. Oikawa;K. Ishida;K. Koyama;K. Koyama
• 通讯作者: K. Koyama

First-order phase transition at the Curie temperature in MnAs and MnAs_<0.9>Sb_<0.>

MnAs 和 MnAs_<0.9>Sb_<0.> 居里温度下的一级相变

• 发表时间: 2006
• 期刊: J. Phys. Soc. Jpn 75
• 作者: K. Koyama;H. Onodera;and K. Watanabe;K. Koyama;K. Koyama;K. Koyama;K. Koyama;F. Ishikawa
• 通讯作者: F. Ishikawa

一次相転移物質MnBiの高温・強磁場磁気特性

初级相变材料MnBi的高温高场磁性能

• 发表时间: 2007
• 期刊: 日本金属学会誌 71
• 作者: R.A.Wach;M.Sugimoto;A.Idesaki;M.Yoshikawa;O. Tegus;K. Koyama;小野木哲也
• 通讯作者: 小野木哲也

First-order phase transition at the Curie temperature in MnAs and MnAs_<0.9>Sb_<0.1>

MnAs 和 MnAs_<0.9>Sb_<0.1> 居里温度下的一级相变

• 发表时间: 2006
• 期刊: J. Phys. Soc. Jpn 75
• 作者: F. Ishikawa;K. Koyama;K. Watanabe;T. Asano;and H. Wada
• 通讯作者: and H. Wada