Ultraprecision Grinding Technique of Fine Ceramics with Micro Loose Diamond Grain

本研究通过研制超精密吸力加工装置，并利用该装置研究磨削新机理，提出了一种微细疏松金刚石微细陶瓷的超精密磨削新技术。通过对载体流动行为的理论分析，探讨了载体的加工机理。本研究的主要结论如下：(1)研制了一种超精密吸力加工装置，该装置是将夹杂着微小疏松磨粒的载体通过被加工件表面上方的限制器吸入，由泵加工而成。(2)利用机械加工技术，实现了毛坯的去除和表面光洁度的改善。(3)限位器间隙为2.0 mm时，加工效果最好，毛坯去除量和表面粗糙度均最大。(4)在节制器中心正下方的下游加工工件表面，在切削量最大的切削点，切削率约为17 nm/min。(5)由于磨粒的干扰，不仅载体流过限制器，而且在限制器中心下游发生空化，从而去除了工件材料。(6)切削量表示为空化、间隙和颗粒数效应的函数，可用超精密加工的三个效应来预测。

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.