| || Cooling ability based integrated quality of laser drilled holes
Author : Pandey, N. D.;Mohandas, T.;Shan, H. S.
Source : Defence Science Journal ; Vol:56(1) ; 2006 ; pp 93-101
Subject : 669 Metallurgy;629.7 Aeronautics
Keywords : Hole quality;Air cooled components;Percussion laser drilling;Nickel base superalloy;SUPERNI 263A;Nd:YAG laser
Abstract : Research aimed at improving the end-product quality in meeting the functional needs is imperative to sustain product development. Aerospace manufacturers are increasingly using percussion laser drilling for producing cooling holes in turbine components made of nickel base superalloys. Laser drilling of superalloys has been initiated at the Defence Metallurgical Research Laboratory, Hyderabad in the last decade keeping in view its uses in Kaveri Gas Turbine Engine programme. Considerable work has been carried out in this direction. Laser-drilled hole's quality issue has been addressed in the past considering separately the shape, precision, and functional characteristics of the laser-drilled holes. In the present investigation, a newer approach for defining hole quality has been reported which takes into account the above hole characteristics for computing cooling ability of the holes. This approach indicates that it is feasible to produce better integrated quality holes through laser drilling.