title: Application of Design of Experiment Method for Thrust Force Minimization in Step-feed Micro Drilling.
abstract: Micro drilled holes are utilized in many of today's fabrication processes.Precision production processes in industries are trending toward the use of smaller holeswith higher aspect ratios, and higher speed operation for micro deep hole drilling. However,undesirable characteristics related to micro drilling such as small signal-to-noise ratios,wandering drill motion, high aspect ratio, and excessive cutting forces can be observedwhen cutting depth increases. In this study, the authors attempt to minimize the thrustforces in the step-feed micro drilling process by application of the DOE (Design ofExperiment) method. Taking into account the drilling thrust, three cutting parameters,feedrate, step-feed, and cutting speed, are optimized based on the DOE method. Forexperimental studies, an orthogonal array L27(313) is generated and ANOVA (Analysis ofVariance) is carried out. Based on the results it is determined that the sequence of factorsaffecting drilling thrusts corresponds to feedrate, step-feed, and spindle rpm. Acombination of optimal drilling conditions is also identified. In particular, it is found in thisstudy that the feedrate is the most important factor for micro drilling thrust minimization.
authors.affiliation: Division of Mechanical Engineering, Inha University, Incheon 402-751, Korea. kdw525@gmail.com.
authors.forename: Dong-Woo
authors.initials: DW
authors.lastname: Kim
authors.affiliation: Division of Mechanical Engineering, Inha University, Incheon 402-751, Korea. chomwnet@inha.ac.kr.
authors.forename: Myeong-Woo
authors.initials: MW
authors.lastname: Cho
authors.affiliation: Department of Mechanical Engineering, University of Incheon, Incheon 402-749, Korea. tiseo@incheon.ac.kr.
authors.forename: Tae-Il
authors.initials: TI
authors.lastname: Seo
authors.affiliation: Nano-Mechanisms Groups, KIMM, Daejeon 305-343, Korea. les648@kimm.re.kr.
authors.forename: Eung-Sug
authors.initials: ES
authors.lastname: Lee
keywords: ANOVA (Analysis of Variance).; Cutting condition optimization; DOE (Design of Experiment); Step-feed micro drilling process; Thrust force