中文摘要：

采用场发射扫描电镜（FESEM）和X射线能谱仪（EDXS）对感应熔炼高锰硅（HMS）中的第二相条纹的形貌和成份进行了研究,发现第二相条纹平行贯穿整个高锰硅晶粒,其条纹宽度约30 nm,间距在5-30 μm内,成份为MnSi.通过高分辨透射电镜（HRTEM）观察到MnSi条纹为短程有序而长程无序的非晶形态.采用选区电子衍射（SAED）确定了高锰硅的晶体结构,结果表明所获得的高锰硅为单一的Mn4Si7相,未观察到高锰硅其它的非公度结构.透射电镜（TEM）结果表明,熔炼的高锰硅经过球磨和热压后产生了大量缺陷和应力畴,与热压之前的熔锭材料相比有明显差异.

英文摘要：

Field emission scanning microscopy （FESEM） and energy-dispersive X-ray spectroscopy （EDXS） were used to study the morphology and composition of secondary phase precipitations in induction-melted higher manganese silicide （HMS）. Striations of the secondary phase were observed in individual HMS crystals with an average interval of 5-30 IJm and a thickness of -30 nm. The chemical composition of the striations was examined and found to be MnSi, which was observed as an amorphous phase by high resolution transmission electron microscopy （HRTEM）. The crystal structure of HMS was determined by selective area electron diffraction （SAED） and the results indicated a single Mn4Si, phase in the as-prepared material and no other incommensurate HMS phases were found. After ball milling and hot pressing many defects and stress fields were observed in the HMS by transmission electron microscope （TEM）, which differentiated substantially from the morphology of the as-melted HMS.