| SnO2 was coated onto the surface of aluminum borate whisker by titration technique. Aluminum whisker reinforced aluminum matrix composite was fabricated by a squeeze casting technique (denoted as SnO2-ABOw/Al), and the volume fraction of the reinforcement was 20%, the matrix was pure-Al alloy .The microstructure of the SnO2 coatings and composites, and the interfacial reaction were studied by use of scanning electron microscope (SEM), transmission electron microscope (TEM), optical microscope (OM), selected area electron diffraction patterns (SADP), and X-ray diffraction (XRD). Mechanical properties of the composites were also studied with tensile tests. The effect of high-heat-treatment on the interface state of the composite was studied.The SnO2 coating changed the interfacial state of composite. The investigation of interface between whiskers and the composite matrix shows that SnO2 coating distributes on the interface of whisker and the matrix generally. The result shows that a chemical reaction exits between SnO2 coating and aluminum during squeeze casting process, product of the reaction areγ-Al2O3 and Sn which has a low melting point. The interfacial reaction between whisker and matrix did not take place during squeeze casting in the composite,so that the whisker could be kept perfectly.The content of SnO2 coating and the temperature of tensile tests have great influence upon the tensile strength of composite. The tensile strength of SnO2-ABOw/Al composite increases with the content of SnO2 coated and the temperature increasing, but decreases when they exceed a certain degree. The result of tensile strength indicates that the ultimate tensile strength (UTS) of the SnO2-ABOw/Al composite is highest when the content of SnO2 coating is 1:20 and the temperature of tensile tests is 300℃.The study on the UTS of the composite shows that SnO2 coating can enhance the composite performance, especially on its high temperature shaping capability.
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