摘要
利用溶胶—凝胶法在SG4工程陶瓷基体上成功制备了Al2 O3 涂层 ;利用差热分析 (DTA)方法对Al2 O3凝胶粉末的热处理过程进行了研究。对线切割、粗磨、精磨、Al2 O3 一次溶胶涂层和Al2 O3 二次溶胶涂层试样的抗弯强度进行了比较 ,并通过观察Al2 O3 一次溶胶涂层和Al2 O3 二次溶胶涂层试样表面和断面的SEM形貌 ,初步分析了表面改性的原因。分析结果表明 :溶胶涂层弥合基体表面微裂纹是提高抗弯强度的根本原因 ;Al2 O3 溶胶二次涂层试样表面质量好于一次涂层试样 ,可以更好地弥合基体表面微裂纹 ,使基体的抗弯强度更高。因此溶胶—凝胶法是陶瓷表面改性的一种有效方法。
The Al 2O 3 coating is prepared by the sol gel process on SG4 engineering ceramics. The heat treatment process of Al 2O 3 gel powders is studied by DTA. The bending strength of the samples after wire EDM cutting, rough grinding, finishing grinding, coating once with Al 2O 3 sol and coating twice with Al 2O 3 sol is tested and compared.The cause of the surface modification is analyzed by observing SEM photographs of surface and section of the samples coated once and twice with Al 2O 3 sol. It is shown that sol coating closing the microcracks of the sample surface is the main reason of increasing the bending strength of substrates. Because the quality of the samples coated twice with Al 2O 3 sol is better than that of the samples coated once with Al 2O 3 sol, the microcracks of the samples coated twice with Al 2O 3 sol can be closed more evidently and make the bending strength higher. In conclusion, sol gel is an effective method for the surface modification of ceramics.
出处
《工具技术》
北大核心
2000年第12期10-12,共3页
Tool Engineering
