(西安理工大學(xué) 材料科學(xué)與工程學(xué)院，西安 710048)
摘 要: 以Lanxide材料的成形工藝控制為目標(biāo)，研究了SiO2表面覆蓋劑在鋁合金熔體直接氧化生長(zhǎng)過(guò)程中的作用。結(jié)果表明有效促進(jìn)Al2O3/Al復(fù)合材料生長(zhǎng)的SiO2加入量為1～6 g/dm2。SiO2能夠顯著促使材料近平面生長(zhǎng)，形成細(xì)化胞狀晶團(tuán)和提高組織均勻度；在覆蓋SiO2的條件下，溫度升高，生長(zhǎng)速度加快的同時(shí)，材料宏觀生長(zhǎng)表面趨于平整，但溫度過(guò)高會(huì)對(duì)組織致密度產(chǎn)生不利影響。
關(guān)鍵字: 直接金屬氧化; Al2O3/Al復(fù)合材料; SiO2表面覆蓋劑; 生長(zhǎng)形貌; 微觀組織
directed oxidation of molten aluminium alloy
（School of Materials Science and Engineering,
Xi′an University of Science and Technology,Xi′an 710048, P.R.China）
Abstract:With the purpose of controlling Lanxide composite forming technique, the effect of SiO2 as a surface dopant on directed oxidation of molten aluminium alloy was studied. The results show that the optimum content of SiO2 is 1～6 g/dm2, which promotes the near-planar surface, the homogenity of microstructure and fine cellular of Al2O3/Al composites. The higher the growth temperature, the faster the oxidation growth, and the smoother the macro-surface of composite；but the density of composite is lowered down when the temperature is excessively high.
Key words: directed metal oxidation; Al2O3/Al composite； SiO2 surface dopant; growth morphology; microstructure
