【摘要】 本文采用Sol-gel工艺制备了不同晶型的氧化铝超微细粉,γ—Al₂O₃、θ—Al₂O₃粒度可达100～200A,呈针状,α—Al₂O₃的平均粒度为500A左右,呈卵圆形。并用FT—IR、XRD、DTA/TG和TEM等手段研究了氧化铝凝胶在煅烧过程中的物相和显微结构的变化。发现氧化铝凝胶在低于300℃时干燥是稳定的,其物相变化过程为γ—AlO（OH）、β—Al（OH）₃（少量）→γ—AlO（OH）（100℃）→γ—Al₂O₃（400℃）→θ—Al₂O₃（1000℃）→α—Al₂O₃（1200℃）。更多还原

【Abstract】 In this paper, different kinds of phase alumina ultrafine powder were prepared by Sol-gel processing. For example, particle size of γ-Al₂O₃ and θ-Al₂O₃ is needle particle of about 100～200A, Particle size of α-Al₂O₃ is spherical particle of about 500A. Phase and microstructure changes of alumina gels in sintering were studied with FT-IR, XRD, DTA/TG and TEMetc. It has been discovered that the solid structure of the dried gel is stable up to at least 300℃,and phase transformation within the solid is bayerite→boehmite→γ- alumina （400℃）→θ-alumina（1000℃）→α-alumina （1200℃）.更多还原