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主要用透射电子显微技术（ＴＥＭ）、电子探针显微分析（ＥＰＭＡ）和选区电子衍射技术（ＳＡＤ）分析了不同冷却条件下ＳｉＣｐ／ＺＡ－２７复合材料的界面特征和结构，发现冷却速度明显影响复合材料的界面结构、界面相组成和复杂金属氧化物的分布以及校晶生长过程的溶质二次分配，且复合材料慢冷时的界面比液淬时的界面复杂得多．复合材料浆液液淬快冷时的界面特征是初生ａ（Ａ１）相与ＳｉＣ颗粒直接机械结合，界面光滑无界面反应产物和中间过渡相及非晶氧化物；电磁搅拌随炉冷却条件下，复合材料界面绝大部分是共晶组织与ＳｉＣ颗粒直接结合，少部分是由共晶组织／岛状非晶组织／ＳｉＣ组成；随炉慢冷时的界面主要是由共晶组织／非晶组织／ＳｉＣ组成，金属基体与ＳｉＣ直接结合的界面非常少．不同冷却条件制备的复合材料的界面存在不同厚度的非晶组织．根据界面形貌和选区电子衍射花样并结合计算机模拟计算，发现部分界面处存在第三相（如ＭｇＡｌ２Ｏ４，Ｍｇ６ＣｕＡｌ７等相），合成电子衍射花样表明这些第三相与ＳｉＣ或基体间无晶体学位相关系．未发现ＳｉＣ与基体间有晶体学位相关系，说明ａ（Ａ１）或共晶相在ＳｉＣ表面成核的可能性较小．复合材料浆液水淬后的基体经微衍射分析得出过饱和?
The interfacial characteristics and structure of SiCp / ZA-27 composites under different cooling conditions were mainly analyzed by transmission electron microscopy (TEM), electron probe microanalysis (EPMA) and selected area electron diffraction (SAD) The interfacial structure, interfacial phase composition and the distribution of complex metal oxides and the solute secondary distribution during the growth of the crystal were significantly affected. The interfacial interface of the composites was much more complex than that of the liquid-quenched interface. The interface characteristics of the composite slurry quenching and fast cooling are that the primary a (A1) phase is directly mechanically bonded with the SiC particles, the interface is smooth and free of interfacial reaction products and intermediate transition phases and amorphous oxides; electromagnetic stirring Most of the material interface is the direct combination of eutectic and SiC particles, and the small part is composed of eutectic / island-like amorphous structure / SiC. When the interface is slowly cooled, the interface mainly consists of eutectic / amorphous / SiC composition, the metal matrix and SiC directly bonded interface is very small. The composite materials prepared under different cooling conditions have different thicknesses of amorphous structure at the interface. According to the morphology of the interface and the selected area electron diffraction pattern and computer simulation, it is found that the third phase (such as MgAl2O4, Mg6CuAl7, etc.) exists at some interfaces and the synthetic electron diffraction pattern shows that these third phases have no crystal correlation with SiC or matrix system. No crystal phase relationship between SiC and matrix was found, indicating that a (A1) or eutectic phase is less likely to nucleate on SiC surface. Composite matrix slurry after water quenching obtained by micro-diffraction analysis supersaturated?