Title: High aspects ratio micro-drilling of super-alloys using ultra short pulsed laser

Authors: Ganesh G. Dongre; Avadhoot Rajurkar; Ramesh Gondil; Jacob Philip

Addresses: Department of Industrial and Production Engineering, Vishwakarma Institute of Technology, Pune, 411 037, India ' Department of Industrial and Production Engineering, Vishwakarma Institute of Technology, Pune, 411 037, India ' Department of Industrial and Production Engineering, Vishwakarma Institute of Technology, Pune, 411 037, India ' PPFF, VSSC, Thiruvanthapuram, 695 586, India

Abstract: The demand for high aspect ratio micro holes is growing day by day. Functional micro-holes are necessary for application areas in aeronautic, automobile, semiconductor and biomedical industries. It requires holes with high contour accuracy and minimum thermal damage. Further, the materials used in these applications are alloys, super alloys and composite materials, which are difficult to cut. Laser-machining has demonstrated outstanding capability to generate high precision micro features. The development of femto, pico-second lasers has provided a precise method for micro-fabrication. In this paper, micro-hole drilling was carried out using a 12 W, Ti-sapphire 50-100 fs laser. Holes are analysed for size and shape. It analyses the effect of pulse duration for SS-316L, Inconel-718 and Ti6Al4V. It also investigates effect of laser drilling techniques like percussion, trepanning and helical. Study concludes that with proper control on beam positioning, beam energy and pulse width one can achieve quality holes using ultrafast lasers.

Keywords: ultra short pulse; aspect ratio; femto and pico-second laser; micro drilling.

DOI: 10.1504/IJPTECH.2019.100955

International Journal of Precision Technology, 2019 Vol.8 No.2/3/4, pp.124 - 141

Received: 29 Jul 2018
Accepted: 06 Feb 2019
Published online: 19 Jul 2019 *

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