Comparative in situ X‐ray and neutron diffraction studies of the phase transitions in a high magnetostriction Fe–27Ga alloy sample have been performed, with heating up to 850°C and subsequent cooling to room temperature. Different structural information (phase content, phase‐transition temperatures, unit‐cell behaviour) is obtained for the bulk sample and its surface, and this fact is discussed here in terms of the difference between the scattering properties of X‐rays and neutrons. In particular, a gallium‐deficient phase with A2‐type structure was found on the surface of the sample. The results demonstrate that conventional X‐ray diffraction methods are insufficient for precise structural analysis of bulk samples of galfenols and cannot be used alone to build their phase diagrams.

中文翻译：

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Fe–27Ga结构的温度演变：原位X射线和中子衍射研究的比较

比较原位在高磁致伸缩相变的透视和中子衍射研究的Fe-27Ga合金样品已经被执行，在加热至850℃，并随后冷却至室温。对于大块样品及其表面，获得了不同的结构信息（相含量，相变温度，晶胞行为），这里就X射线和中子散射特性的差异讨论了这一事实。尤其是在样品表面发现了具有A2型结构的镓缺乏相。结果表明，常规的X射线衍射方法不足以精确地对加苯酚的大量样品进行结构分析，并且不能单独用于建立其相图。