MICRO-MACHINING OF CERAMICS USING ABRASIVE-JET TECHNOLOGY

本计画系探讨微磨料射流加工之基本特性与应用。研制了一种用于陶瓷材料微细加工的微细自对准加工装置。它具有载气压力比常规装置高3-4倍，磨料与载气混合均匀等优点。首先，用激光多普勒测速仪测量了磨料颗粒在气流中的速度。很明显，磨料颗粒被加速到100和200 m/s之间的速度，这大约是声速的60%。其次，提出了一种工件上磨料分布的测量方法。采用片状激光光源和CCD摄像单元。该方法的原理是基于衍射光强法，并应用图像处理技术来获得分布。很明显，磨料散布在比喷嘴横截面更大的区域上。通过对AlN、SiC、Si_3N_4、玻碳、ZiO_2和玻璃等陶瓷材料的加工试验，揭示了该方法的加工特性。此外，对于微AJM应用，尝试了微钻孔、图案加工和过程中修整。微细自对准技术在脆性材料的微细加工中表现出了优异的性能。

This project deals with the fundamental characteristics and applications of a micro-abrasive jet machining (micro-AJM). The micro-AJM device, which is for micro-machining of ceramics, was developed. It has advantages that the pressure of carrier gas is 3-4 times higher than that of a normal device, and that the mixing of abrasives and carrier gas is uniform.First, the velocity of abrasive particles, which are accelerated with a gas stream, was measured with laser Doppler velocimeter. It is clear that the abrasive particles were accelerated to a velocity of between 100 and 200 m/s, which is approximately 60% of sound speed. Second, a distribution measuring method of attacking abrasive onto the workpiece was developed. Sheet laser light source and CCD camera unit were used. The principle of this method is based on the diffraction light intensity method and image processing technique is applied to get the distribution. It was clear that the abrasives were spread over larger area than the cross section of the nozzle. Information of the velocity and the abrasive distribution is useful in selecting the optimal AJM conditions and in the designing the nozzle shape.Machining tests of ceramics (AlN,SiC,Si_3N_4, glassy carbon, ZiO_2 and glass) were performed and the machining characteristics were revealed. Furthermore, for micro-AJM applications, micro-drilling, pattern machining, and in-process dressing were tried. Micro-AJM technology demonstrated the excellent performance in the micro-machining of brittle materials.