Magnetostriction and structural characterization of Fe-Ga bulk alloy prepared by copper mold casting  

铜模铸造块体Fe-Ga合金的磁致伸缩性能和结构特征(英文)

作　　者：胡勇[1,2] 丁雨田[1,2] 张艳龙[1] 王国斌[1] 周质光[1] 

机构地区：[1]兰州理工大学 甘肃省有色金属新材料省部共建国家重点实验室,兰州730050 [2]兰州理工大学温州泵阀研究院,温州325105

出　　处：《Transactions of Nonferrous Metals Society of China》2012年第9期2146-2152,共7页中国有色金属学报（英文版）

基　　金：Project (11004091) supported by the National Natural Science Foundation of China;Project (Y4090219) supported by the Natural Science Foundation of Zhejiang Province, China;Project (0916RJZA025) supported by the Natural Science Foundation of Gansu Province, China;Project (Q201104) supported by the "Hongliu Outstanding Youth" Foundation of Lanzhou University of Technology, China

摘　　要：Rapidly solidified Fe100-xGax （x=16-20） alloy rods were prepared by induction melting and copper mold casting under the protection of inert gases. The optical microscopy observation shows that the large and elongated columnar grains grow along the radial direction, which is parallel to the temperature gradient direction. The preferred orientation texture along the axial direction of the rod was detected by XRD. With the increase of Ga content, the saturation magnetization （Ms） of the alloys decreases distinctly and the dynamic response in low magnetic field increases drastically, the maximum longitudinal saturation magnetostriction for as-cast Fe82Ga18 alloy rods is 92×10-6 under an applied magnetic field strength of 30 kA/m. The large magnetostriction of Fe100-xGax alloys is attributed to the rapidly solidified disordered A2 phase and the high concentration of short range order of Ga atom clusters, which are arranged in the direction and finally trigger the formation of modified-DO3 structure, just as shown by the split of the （200） diffraction peak. Ordered DO3 phase is not conducive to the magnetostriction.采用惰性气体保护下的感应熔炼铜模吹铸方法,制备具有非平衡快速凝固组织、晶粒沿温度梯度取向生长的Fe100-xGax(x=16～20)合金棒。XRD分析判定棒材主要为无序A2相结构且具有<110>轴向择优取向。随着Ga元素含量的增加,合金的饱和磁化强度明显降低,低场动态响应迅速增加。快速凝固获得的 Fe82Ga18合金棒的纵向饱和磁致伸缩在30kA/m磁场强度下为92×10-6。吹铸法制备的Fe100-xGax(x=16～20)合金棒材大的磁致伸缩性能源自快速凝固过程中所保留下来的高温无序A2相和合金内部所具有的大量沿<100>方向排列的短程有序富Ga原子团簇,这些富Ga团簇最终诱发畸变 DO3相的生成,正如(200)衍射峰发生劈裂所示。有序化转变生成的DO3相对该合金的磁致伸缩性能不利。

关 键 词：MAGNETOSTRICTION rapid solidification Fe-Ga alloy oriented polycrystalline microstructure 

分 类 号：TG291[金属学及工艺—铸造]