CAJ | 학술논문

采用交流碳弧法高效合成碳包碳化铁纳米晶磁性微粉，磁性微粉产率达90％以上.用热重分析法(TG)测得磁性微粉中Fe的质量分数为17.5％.X射线衍射(XRD)分析结果表明，在碳包碳化铁微粉中存在FeaC和FesC2两种结构形式，不含纯Fe晶粒，碳层结构与石墨相似.在透射电镜(TEM)下观察了纳米晶的形貌和粒径分布，碳化铁纳米晶尺寸分布在3～10 nm，并呈颗粒状分散在碳层中，碳层为巴基管和巴基葱的堆积体，形状各异，尺寸分布在几十纳米到几微米之间.讨论了碳包碳化铁纳米晶的形成机理.测定了磁性微粉的磁滞回线，其饱和磁感应强度Bs，剩磁Br和矫顽力Hc分别为2.6×10-2T，2.5×10-3T和5.52 kA/m.
채용교류탄호법고효합성탄포탄화철납미정자성미분，자성미분산솔체90％이상.용열중분석법(TG)측득자성미분중Fe적질량분수위17.5％.X사선연사(XRD)분석결과표명，재탄포탄화철미분중존재FeaC화FesC2량충결구형식，불함순Fe정립，탄층결구여석묵상사.재투사전경(TEM)하관찰료납미정적형모화립경분포，탄화철납미정척촌분포재3～10 nm，병정과립상분산재탄층중，탄층위파기관화파기총적퇴적체，형상각이，척촌분포재궤십납미도궤미미지간.토론료탄포탄화철납미정적형성궤리.측정료자성미분적자체회선，기포화자감응강도Bs，잉자Br화교완력Hc분별위2.6×10-2T，2.5×10-3T화5.52 kA/m.
A highly effective method for preparation of carbon-coated iron carbide nanocrystals by AC carbon arc discharge was studied,the yield of magnetic micro powder was over 90％.The result of thermogravometric analyses (TG) (＞800℃,O2,5℃/min) indicated that there was 17.5％ of Fe wrapped by graphite carbon in the magnetic micro powder.The structural characterization by X-ray diffraction(XRD) and transmission electron microscopy(TEM) revealed that Fe3C and Fe5C2 particles were wrapped by graphite carbon,no evidence of α-Fe was observed.The size of the wrapped iron carbide particles was typically in the range 3－10 nm.The formation mechanism of carbon-coated iron carbide nanocrystals was discussed.The magnetic hysteresis loop(B-H) at room temperature was investigated,it showed that Bs=2.6×10-2 T,Br=2.5×10-3 T,Br/Bs=9.7％,Hc=5.52 kA/m.