Atomic occupation and role of Cr atoms in Cr-doped Ni43Co7Mn39Sn11 magnetic shape memory alloys

作者：Wang, Songwang; Yang, Ruoou; Lu, Guangduo; Yi, Lizhi; Liu, Min; Xu, Yunli^*; Pan, Liqing^*

来源：Journal of Alloys and Compounds, 2022, 929: 167315.

DOI：10.1016/j.jallcom.2022.167315

• Heusler alloy
• Atomic occupation
• Extended X-ray absorption fine structure
• Ferromagnetic resonance

The atomic occupation, magnetic properties and the relationship between them of Ni43Co7Mn39-xCrxSn11(x = 0, 0.4, 0.6, 0.8, 1.0, 1.2 at%) alloys have been systematically investigated. To elucidate the oc-cupancy of Cr atoms, extended X-ray absorption fine structure (EXAFS) is performed and Cr K-edge EXAFS analysis determines that Cr atoms occupy Y site of the Ni43Co7Mn38Cr1Sn11 sample. Ferromagnetic re-sonance shows the evolution of the microscopic magnetic properties of the magnetic atoms with the in-crease of Cr doping content, which further confirms the Y-site occupation of Cr atoms. The experimental results show that in the Ni43Co7Mn39Sn11 system, Cr doping replaces Mn at the Y site, breaking the sym-metry of the crystal field of Mn atoms at the Z site, reducing the atomic displacement potential. The doping of Cr atoms significantly enhances the driving force of its magnetic field-induced martensitic transforma-tion.

• 单位
  中国科学院; 华中科技大学