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研究了高纯氮气下先后进行580℃保温8h、1700℃保温3h热处理后Al-MgAl2O4复合材料的物相组成和反应机理.结果表明:经580℃保温8 h后,Al-MgAl2O4复合材料形成分层现象,即外层区含金属铝-氮化铝壳核结构.当温度升至某一特定值时,金属铝-氮化铝壳核结构破裂,金属铝Al(l/g)溢出/逸出,与N2和O2分别反应生成AlN和Al2O(g),促进化学计量比的镁铝尖晶石(MgAl2O4)分解形成富氧化铝的镁铝尖晶石(Al2O3-rich spinel)和镁蒸气(Mg(g)).一方面,AlN与富氧化铝的镁铝尖晶石形成MgAlON尖晶石;另一方面,AlN与Mg(g)和O2发生固溶体反应生成氮化铝固溶体,(Mg,Al)(N,O).内层区的材料物相组成不同于外层区,含有许多由气-气反应Al2O(g)+O2(g)+N2(g)+Mg(g)→MgAlON(s)或Al(g)+O2(g)+N2(g)+Mg(g)→MgAlON(s)生成的片状MgAlON;此外,内层区富氧化铝的镁铝尖晶石没有进一步转变为MgAlON尖晶石.“,”The phase composition and reaction mechanism of aluminum-spinel(Al-MgAl2O4)composite were investigated after being treated at 580℃for 8 h and 1 700℃for 3 h in flowing high purity nitrogen.The results show that after being treated at 580℃for 8 h,the Al-MgAl2O4 composite forms an area phenomenon with the aluminum-aluminum nitride(Al-AlN)core-shell structure in the outside area.When the temperature increases up to a critical value,the Al-AlN core-shell structure in the outside area breaks,Al(l/g)reacts with N2 to form AlN and with O2 to form Al2O(g).This process prompts formation of an MgAl2O4 spinel with stoichiometric ratio that allows decomposition into Al2O3-rich spinel and Mg(g).On the one hand,AlN reacts with Al2O3-rich spinel to form MgAlON spinel,and on the other hand,AlN is transformed into(Mg,Al)(N,O)through the solid solution reaction of Mg(g)and O2(g)into AlN.Phase composition of the inside area is different from the outside area in which MgAlON with flake crystal morphology forms via a gas-gas phase reaction:Al2O(g)+O2(g)+N2(g)+Mg(g)→MgAlON(s)or Al(g)+O2(g)+N2(g)+Mg(g)→MgAlON(s)in which Al2O3-rich spinel doesn't further form MgAlON spinel.