论文标题
微观结构变化影响了散装纳米晶材料的磁性行为
Microstructural Changes Influencing the Magnetoresistive Behavior of Bulk Nanocrystalline Materials
论文作者
论文摘要
中小型铁磁含量的散装纳米晶材料是使用室温下的高压扭转的严重塑性变形产生的。发现巨型磁扰性行为作为变形材料，通过使用热处理来调整微结构，进一步改善了这一材料。通过原位同步加速器衍射测量值评估了足够的退火温度范围。经过热处理的Cuco材料在300℃下退火后显示出更大的巨型磁磁性，而对于CUFE来说，这种退火温度过高，降低了磁磁性特性。通过电子显微镜和EXATU同步加速器衍射测量值观察到的微观结构进化，讨论了通过热处理的磁扰性的改善。
Bulk nanocrystalline materials of small and medium ferromagnetic content were produced using severe plastic deformation by high-pressure torsion at roomtemperature. Giant magnetoresistive behavior was found for as deformed materials, which was further improved by adjusting the microstructure with thermal treatments. The adequate range of annealing temperatures was assessed with in-situ synchrotron diffraction measurements. Thermally treated CuCo materials show larger giant magnetoresistance after annealing for 1 h at 300C, while for CuFe this annealing temperature is too high and decreases the magnetoresistive properties. The improvement of magnetoresistivity by thermal treatments is discussed with respect to the microstructural evolution as observed by electron microscopy and ex situ synchrotron diffraction measurements.
