摘要
氧化铝在许多工业领域已经得到了广泛的应用 ,随着新材料科学和先进制造技术的发展 ,对陶瓷复合材料的性能要求日益提高 ,为了提高氧化铝基陶瓷复合材料的力学性能 ,需要提高氧化铝的纯度和表面活性、降低其粒度 ,对此传统的氧化铝制备方法不能满足这一要求。溶胶—凝胶法是制备纳米粉末的重要技术之一 ,作为一种湿化学合成方法 ,具有设备简单 ,工艺易于控制 ,粉末纯度和均匀度高 ,成本低等优点 ,在制备涂层以及涂层复杂形状零件方面有很大的优越性。本文以异丙醇铝 (Al(C3 H7O) 3 )为原料 ,用溶胶—凝胶法制备出了纳米氧化铝 (Al2 O3 )粉末。通过X射线衍射分析和差热分析 ,研究了由凝胶至α -Al2 O3 粉末的转变过程以及影响粉末性能的因素。研究表明 ,溶胶—凝胶法制备的胶体在 12 0 0℃的温度下可以完全转化为纳米α -Al2 O3 ,并且具有较高的质量密度 ,所制备的纳米α -Al2 O3 具有较理想的晶体结构类型 ,未发现其它相或杂质 ,这表明溶胶—凝胶法是制备高纯度纳米陶瓷粉末的有效技术。
Alumina (Al 2O 3) has been widely applied in great many different industrial areas. With the development of new material science and advanced manufacturing technology, the need for improving the purity, fine grain size, surface activation of alumina has long been recognized to increase the mechanical properties of alumina-based composites such as ceramic materials. The alumina powders prepared with conventional methods can not satisfy this high requirement. The sol-gel method is one of the most important techniques for preparing high quality nanoscale powders since it provides a high-purity, low temperature synthesis and especially a precise composition control. On the other hand, the sol-gel method can be used to coat other materials to improve their surface performance. It can overcome many of the disadvantages of conventional techniques because it is simple, less expensive and allows coating of complex geometry. The nanoscale alumina (Al 2O 3) powders were prepared from the raw materials of aluminium-iso-propoxide (Al(C 3H 7O) 3) with the sol-gel technology. The transformation process from the gelata to the alpha alumina powders has been investigated by means of X-ray diffraction analysis and differential thermal analysis. All the factors that affect the performance of the alpha alumina powders were also discussed in detail. It was found that the gel could be completely transformed into α-Al 2O 3, and sintered to relatively high density at 1200℃, as the activity of colloidal particles was very high. The prepared nanoscale alumina was polycrystalline and isotropic and no weak phase was found in the alumina powders. It was verified that the sol-gel method is a promising technique for preparing nanoscale ceramic powders.
出处
《金刚石与磨料磨具工程》
CAS
2002年第1期22-25,共4页
Diamond & Abrasives Engineering
基金
山东省优秀中青年科学家科研奖励基金 (9812 )
山东省教育厅 (J98A5 6 )资助
关键词
氧化铝
纳米粉末
溶胶-凝胶法
制备
异丙醇铝
Sol-gel technology Aluminium-iso-propoxide α-alumina Nanoscale alumina
