Improvement of the tensile strength of Al18B4O33w/Al composite at elevated temperatures by change of interfacial state

In general, it is very difficult to obtain obviously reinforced effect in discontinuously reinforced aluminum matrix composites at the temperature above 400 degrees C. In the present study, we report an effective method to improve the high-temperature tensile strength of Al(18)B(4)O(33)w/Al composite by change of interfacial state. The pure aluminum matrix composites reinforced by Al18B4O33W with different ZnAl2O4 coating contents were fabricated by squeeze casting. The results indicate that ZnAl2O4 coating of the whiskers can effectively improve the high-temperature tensile strength of Al(18)B(4)O(33)w/Al composite, although the tensile strength of the composite decreases with increasing the tensile temperature. On the basis of fractograph analysis, the fracture mechanism of the composites at elevated temperatures was investigated. (C) 2007 Elsevier B.V. All rights reserved.