Percussion Laser-Drilled Holes: Characteristics and Characterization Procedure

Abstract

Percussion laser drilling, being a thermal process, produces holes having widely differing characteristics than that of the mechanically drilled holes. In the present study, on the percussion laser drilling of through holes in a nickel-based superalloy (SUPERNI 263A), 21 characteristics were identified, and the methods of their determination were proposed. The effect of peak power of laser pulses on the identified hole characteristics were studied.

Keywords:

• Hole characteristics
• Laser drilling
• Nd:YAG laser
• Nickel-based superalloy
• Peak power of laser pulses
• Percussion laser drilling
• SUPERNI 263A

ACKNOWLEDGMENTS

The authors thank Dr. D. Banerjee, CC (R&D), DRDO for continuous encouragement and support. We gratefully thank Dr. A.M. Srirama Murty, Director, DMRL for invaluable support and encouragement. Useful discussions with Dr. P. Ghosal and the help extended by the members of Laser, Metallography, SEM, and Photography sections of DMRL, and CAE and PD Laboratories of MIED, IIT, Roorkee are thankfully acknowledged. One of the authors (NDP) is grateful to Dr. A. Bharti, DOM for introducing him to the field of Laser Processing. The work is published with the kind permission of the Director, DMRL and was supported by the general DRDO grants.