Develop Cutting Force of Micro-Via Drilling by Oblique Cutting and Experiment

• Main Authors: Yi-Wei Chen, 陳一葳
• Other Authors: Chih-Tsong Su
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/70207038279802415832

碩士 === 國立高雄第一科技大學 === 機械與自動化工程所 === 92 === The micro-drill usually breaks in drilling as a result of too great a drilling force; the reason is due to the characteristic of its small diameter and high aspect ratio. This study uses the oblique cutting model and the orthogonal cutting model coupled with the development of a thin shear zone cutting analysis to predict the thrust and torque. Not only the factorial design of experiment is used to investigate the influence of machining parameter to cutting force, but also this study utilizes 24-1 factorial design to arrange the experiment of micro-drill tool geometry and cutting force. The result of experiment comes out a regression equation through “analysis of variance”, “regression analysis” and “residual analysis”. The response surface diagram is used to analyze the impact of factors and interaction of factors to cutting force. Finally, this study optimizes the design of micro-drill tool geometry and verifies the accuracy of this experiment. According to the result, the thrust and the torque increase with the raise of feed speed if the rotational speed is constant. On the contrary, the thrust and the torque decrease with the raise of the rotational speed if the feed speed is constant. The investigation also shows that the thrust decreases with small point angle, web thickness and large helix angle. However, the torque decreases with large point angle, helix angle and small web thickness. Beside, the interaction of point angle and helix angle affects the torque significantly. The result of this research can reduce the chance of broken micro-drills due to the wrong arrange of machining parameter. It also optimizes the design of micro-drill tool geometry to reduce the production of cutting force.