The structure, internal friction (IF) behavior, resistivity and magnetostriction property of Fe-18Ga alloy were systematically analyzed in this investigation. In the IF spectra of Fe-18Ga alloy covered from room temperature (RT) to 800 °C, a prominent IF peak (labeled as P_tr peak) was observed in the high temperature range 530 °C–690 °C besides the reported IF peak related with grain boundary relaxation in the moderate temperature range 400 °C–530 °C. The peak position of P_tr peak hardly changes with measuring frequency, implying that its mechanism is most possibly related with phase transition. Considering from the wide peak shape, P_tr peak can be decomposed into two components: the lower temperature P_tr1 peak located around 530 °C–605 °C and the higher temperature P_tr2 peak located around 605 °C–690 °C. Combined with calculated phase diagram, resistivity and magnetostriction analysis, the mechanism of P_tr peak was suggested to originate from the order-disorder phase transition related with Ga atom distribution in Fe-18Ga alloy: P_tr1 peak was ascribed to D0₃→B2 transition and P_tr2 peak was ascribed to B2→A2 transition, respectively.

本研究对Fe-18Ga合金的组织，内摩擦（IF）行为，电阻率和磁致伸缩性能进行了系统的分析。在从室温（RT）到800°C的Fe-18Ga合金的IF光谱中，除了报道的IF，在530°C–690°C的高温范围内还观察到了显着的IF峰（标记为P _tr峰）。在400°C–530°C的中等温度范围内，与晶界弛豫相关的峰。P _tr峰值的峰值位置几乎不会随测量频率变化，这表明其机理最可能与相变有关。从宽峰形状考虑，P _tr峰可分解为两个分量：较低的温度P_tr1峰值位于530°C–605°C左右，较高的温度P _tr2峰值位于605°C–690°C左右。结合计算出的相图，电阻率和磁致伸缩分析，认为P _tr峰的机理起源于与Fe-18Ga合金中Ga原子分布有关的有序-无序相变：P _tr1峰归因于D0 ₃ →B2跃迁和P _TR2峰分别归属于B2→A2过渡。