Mechanism study of micro-electrical discharge drilling method during micro-dimpling

  • PDF / 1,793,255 Bytes
  • 11 Pages / 595.22 x 842 pts (A4) Page_size
  • 97 Downloads / 203 Views

DOWNLOAD

REPORT


DOI 10.1007/s12206-020-0530-8

Journal of Mechanical Science and Technology 34 (6) 2020 Original Article DOI 10.1007/s12206-020-0530-8 Keywords: · Electrical discharge drilling · Microdimple · Cutting mechanism · Cutting force

Mechanism study of micro-electrical discharge drilling method during micro-dimpling Sang Tae Jung1, Rendi Kurniawan2, S. Thirumalai Kumaran3, In Jun Yoon2 and Tae Jo Ko2 1

Correspondence to: Rendi Kurniawan [email protected]

Citation: Jung, S. T., Kurniawan, R., Kumaran, S. T., Yoon, I. J., Ko, T. J. (2020). Mechanism study of micro-electrical discharge drilling method during micro-dimpling. Journal of Mechanical Science and Technology 34 (6) (2020) ?~?. http://doi.org/10.1007/s12206-020-0530-8

Received November 18th, 2019 Revised

February 24th, 2020

Pohang Accelerator Laboratory, Pohang University of Science and Technology, Pohang-Si 37673, Ko2 rea, Precision Machining Laboratory, Department of Mechanical Engineering, Yeungnam University, 3 Gyeongsan-Si 38541, Korea, Faculty of Mechanical Engineering, Kalasalingam University, Tamil Nadu, Krishnankoil 626-126, India

Abstract

This paper reports the cutting mechanism in micro-electrical discharge drilling (µEDD) during a micro-dimpling process. A combination of fundamental micro-drilling and micro-electrical discharge machining (µEDM) is considered the main mechanism in the µEDD process. First, the cutting force in micro-drilling was modeled on a chisel and lip section based on a mechanistic model of the oblique cutting. Second, the model of the µEDM was also included based on uniform heat flux. Experiments of a micro-dimple were carried out on a titanium alloy (Ti6Al4V) to confirm the model validity. The validation confirms that the proposed cutting force model can be applied to predict the thrust force during micro-dimpling under µEDD. In addition, a micro-dimple morphology is also discussed.

Accepted April 8th, 2020 † Recommended by Editor Hyung Wook Park

1. Introduction

© The Korean Society of Mechanical Engineers and Springer-Verlag GmbH Germany, part of Springer Nature 2020

This paper proposes the cutting mechanism during the fabrication of a micro-dimple on a titanium alloy using micro-electrical discharge drilling (µEDD). The µEDD method is a combination of two methods: Micro-drilling [1] and micro-electrical discharge machining (µEDM) [2]. The micro-dimple was manufactured using a rotating micro-drilling tool (drill bit) and a discharge plasma spark to reduce the cutting energy during the micro-dimpling process. The fabrication of a micro-dimple on the surface brought benefits, such as a reduced coefficient of friction and wear between two lubricated contact surfaces [3]. In most cases, a micro-dimple was manufactured on a soft material, such as aluminum alloy. Mechanical manufacturing methods, such as vibration texturing [4], ball-end milling [5], and elliptical vibration-assisted cutting [6] are used frequently to fabricate micro-dimples on soft materials. On the other hand, there are few publications on the fabrication of