Preparation of ultrafine α-Al_2O_3 powders by catalytic sintering of ammonium aluminum carbonate hyd

来源 :Journal of Central South University of Technology(English Ed | 被引量 : 0次 | 上传用户:shuibizi
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The precursor of ammonium aluminum carbonate hydroxide was synthesized by using aluminum sulfate(Al_2(SO_4)_3) and ammonium carbonate((NH_4)_2CO_3). The effects of α-Al_2O_3 seeds and mixture composed of α-Al_2O_3 and ammonium nitrate, as well as multiplex catalysts (AT) on phase transformation of alumina in sintering process were investigated respectively. The results show that the α-Al_2O_3 seeds and the mixture of α-Al_2O_3 and ammonium nitrate can lower the phase transformation temperature of α-Al_2O_3 to different extents while the particles obtained agglomerate heavily. AT has great potential synergistic effects on the phase transformation of alumina and reduces the phase transformation temperature of α-Al_2O_3 and the trends of necking-formation between particles. Therefore the dispersion of powder particles is improved significantly. The precursor of ammonium aluminum carbonate hydroxide was synthesized by using aluminum sulfate (Al_2 (SO_4) _3) and ammonium carbonate ((NH_4) _2CO_3). The effects of α-Al_2O_3 seeds and mixture composed of α-Al_2O_3 and ammonium nitrate, as well The results show that the α-Al 2 O 3 seeds and the mixture of α-Al 2 O 3 and ammonium nitrate can lower the phase transformation temperature of α-Al 2 O 3 to different extents while the particles obtained agglomerate heavily. AT has great potential synergistic effects on the phase transformation of alumina and reduces the phase transformation temperature of α-Al 2 O 3 and the trends of necking-formation between particles.
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