材料期刊网

<正> 一、前言 目前,电子显微镜作为研究材料性能的一个有力手段,正在开辟它独立的应用领域。这是因为电镜是能对原子排列、晶体微观结构、各种晶体缺陷进行观察的唯一手段。并且,还因为它能分析出包含缺陷的微区成分;有时,也能分析其状态。 但是为了得到这样高分辨率的图象,使用目前100kV(或200kV)商品电镜时,允许观察

Ⅰ. IntroductionⅡ. Advantages of HVEM2.1 Enhancement of resolution for thicker specimen2.2 Improvement of penetrating power2.3 Broadening the scope of thicker specimen observation2.4 Improvement of visibility and contrast of crystal defects and dislocation image2.5 Accuracy of selected area diffraction2.6 Irradiation damge, bombardment damage in metals and ionization damage in organic substances2.7 Critical voltage effects2.8 Special imaging techniques to improve contrastr in HVEM2.9 High voltage scanning transmission electron microscope2.10 In-situ observation of dynamic processⅢ.Specimen, its treatment and observation conditions 3.1 Specimen3.2 Orientation control of specimen3.3 Condition of specimen treatingⅣ. Identification of crystal defects and their fundamental properties4.1 Point defects and their migration4.2 Dislocation4.3 Dislocation loop4.4 Stacking fault4.5 Small angle grain boundary and coincidence grain boundary4.6 precipitates and inclusionⅤ.Relationship between microdtructure and macro-properties5.1 Mechanical properties5.2 Recovery and recrystallization5.3 Phase transformation, nucleation and growth of precipitates5.4 Magnetic domain, structure of domain wall and its temperature dependence5.5 Property of semiconducting grains and crystal defects5.6 Electron irradiation damage5.7 Application of critical voltage effect to the study of material properties5.8 Illustration of in-situ observation Concluding remarks