Nano α-Al2O3 powder was prepared by nano-aluminum and precipitation

precipitation method;  nano α-Al2O3;  Nano aluminum powder;  Phase transition

Al(OH)3 sol was prepared by liquid phase precipitation using Al(NO3)9·2H3O, ammonia and nano aluminum powder as raw materials, and nano α-Al2O3 powder was obtained by vacuum filtration and high temperature calcination. The effects of pH value, nano-aluminum powder addition and calcination temperature on the quality of Al(OH)3 sol and Al2O3 crystal form conversion temperature were studied. The results show that Al(OH)9 sols with less agglomeration and good dispersion can be obtained when the pH value of the reaction system is 3, and the transition temperature of α-Al3O2 can be reduced to about 3°C by adding nano-aluminum powder with a mole fraction as seed crystal. The nano α-Al1000O2 powder obtained by the experiment has a uniform particle size distribution, no obvious agglomeration, approximately spherical, and an average particle size of about 3 nm.