Zhao Jingzhong,Gao Jiqiang,Jin Zhihao
(State Key Laboratory for Mechanical Behavior of Materials,Xi'an Jiaotong University,Xi'an 710049,China)
Abstract:The effect of SiO2 surface dopant on directed oxidation of alloy Al-Zn-Si at high temperature in air was studied by thermogravimetric experiments.The results show that SiO2 markedly shortens the incubation period of Al-Zn-Si alloy directed oxidation and the growth time of Al2O3/Al composites. In addition, it is observed thatAl2O3/Al composite grows with gloss cellular front when SiO2 surface dopant
is added, which facilitates raising the fine cellular of Al2O3/Al composite, the homogeneity of microstructure and relative density of the material. The optimum content of SiO2 for promoting the oxidation growth of Al2O3/Al composites approaches to 12 mg/cm 2.
Keywords:composite;directed oxidation;thermogravimetric experiment;SiO2 dopant