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用Ｘ射线衍射、电子显微镜、Ｘ射线光电子能谱和振动样品磁强计对在１０和１８ｋＰａ压强的氩气中以铁和碳作为电极，通过交流电弧法制备的微粒进行了分析。结果表明，用此方法可制取纳米量级的合金微粒。所形成的微粒有两类：一类是六方ＦｅＣ微粒，另一类为立方铁微粒。铁微粒具有心部为α-Ｆｅ、外部为Ｆｅ３Ｏ４、ＦｅＯ及非晶的ＦｅＯ（ＯＨ）的多层结构。在不同压强下，Ｃ进入铁微粒的程度不同，从而使铁微粒的抗氧化能力不一样，因此α-Ｆｅ的含量不同。此外，由于碳对铁的晶化性质的影响，可使铁微粒的粒径随之改变。在两种不同压强下制得的Ｆｅ—Ｃ微粒由于α-Ｆｅ含量和粒径的不同，其比饱和磁化强度 ｓ和矫顽力Ｈｃ也有差异。由于Ｆｅ—Ｃ微粒中的铁微粒的结构随温度的变化，磁化强度ｓ从２００—２８０℃出现异常增加。
The particles prepared by the alternating current arc method were analyzed by X-ray diffraction, electron microscopy, X-ray photoelectron spectroscopy and vibrating sample magnetometers using iron and carbon as the electrodes in argon at pressures of 10 and 18 kPa. The results show that nano-sized alloy particles can be prepared by this method. There are two types of particles formed: one is hexagonal FeC particles and the other is cubic iron particles. The iron particles have a multilayered structure with α-Fe in the center and Fe3O4, FeO and amorphous FeO (OH) in the outside. Under different pressures, C enters the iron particles to different degrees, so that the anti-oxidation ability of the iron particles is not the same, so the α-Fe content is different. In addition, due to the effect of carbon on the crystallization properties of iron, the particle size of the iron particles can be changed accordingly. Fe-C particles prepared under two different pressures have different specific saturation magnetization s and coercivity Hc due to the different α-Fe content and particle size. Due to the change of the structure of iron particles in Fe-C particles with temperature, the abnormal increase of magnetization s from 200-280 ℃.