Variable angle laser drilling of thermal barrier coated nimonic

This paper provides a comprehensive description and discussion of the problems that occur during angled percussion laser drilling of thermal barrier coated (TBC) nimonic. Laser parameter sets covering a broad range of energies and pulse widths were used to drill holes normal to and at a high angle of incidence (low glancing angle) to the material surface. The dimensional characteristics and interface condition of these holes were analysed and critically discussed. Mechanisms for the formation of the delamination are proposed.