Ultraprecision Grinding Technique of Fine Ceramics with Micro Loose Diamond Grain

本研究通过研制一种超精密吸加工装置，并利用该装置对新型磨削机理进行研究，提出了一种具有微松散金刚石颗粒的精细陶瓷的超精密磨削新技术。此外，从理论上分析了载体的流动特性，探讨了加工机理。研究得出的主要结论如下：(1)研制了一种超精密吸加工装置，该装置通过工件表面正上方的节流器吸走混合有微松散磨粒的载体，用泵对其进行加工。(2)通过机加工技术，产生了去渣，提高了表面光洁度。(3)节流器间隙为2.0mm时，加工效果最好，除渣量最大，表面粗糙度降低也最大。(4)限流器正下方下游的工件表面进行加工，在产生最大去除率的加工点，去除率约为17nm/min。(5)在载流子流过节流器的同时，在节流器中心下游产生空化，磨料颗粒的干涉将工件材料移出。(6)坯料去除率是空化效应、间隙效应和晶粒数效应的函数，可通过超精密加工的三种效应进行预测。

In this reserch, a new ultraprecision grinding technique of fine ceramics with micro loose diamond grain is proposed by development of a ultraprecision sucking machining apparatus and investigating the new grinding mechanism with the apparatus. Furthermore, machining mechanism is investigated by analyzing flowing behavior of carrier theoretically. Main conclusions obtained in this research are as follows : (1) The ultraprcision sucking machining apparatus, which carrier mixed with micro loose abrasive grains is sucked through the restrictor just above workpiece surface to be machined by a pump, is developed. (2) Stock removal is generated and surface finish is improved with the machining technique. (3) In the case of 2.0mm in clearance of restrictor, highest machining effect is occurred, so that both stock removal and decrease of surface roughness are maximum. (4) Workpiece surface downstream from just under the center of restrictor is machined, and at the machining point generating maximum stock removal, stock removal rate is about 17nm/min. (5) Workpiece material is removed by interference of abrasive grains with not only flowing of carrier through a restrictor but also cavitation occurring downstream from the center of restrictor. (6) Stock removal is expressed as a function of cavitation, clearance and grain number effect, and it can be predicted by three effect of the ultraprecision machining.