Product Code: PIC2008_1102

A Statistical Model for Research on the Focal Position Effect on the Taper of Laser Drilling
Authors:
Yinzhou Yan, Institute of Laser Engineering, Beijing University of Technology; Beijing Peoples Republic of China
Lingfei Ji, Institute of Laser Engineering, Beijing University of Technology; Beijing Peoples Republic of China
Yijian Jiang, Institute of Laser Engineering, Beijing University of Technology; Beijing Peoples Republic of China
Yong Bao, Institute of Laser Engineering, Beijing University of Technology; Beijing Peoples Republic of China
Presented at PICALO 2008

The relationships between focal position and diameter or taper of holes drilled by CO2 laser in ceramics were investigated by a new method named equivalent stack plate method(ESPM).The diameter of holes in different depth can be accurately measured by the new method. The present study reported a statistical analysis to study the effects of the focal position on the quality of the drilled holes and optimization of the processing parameter. The study was conducted based on the statistical experiments with the variable focal position from +1mm to -3mm. Then the relationship between focal position and diameter in different depth and corresponding mathematical model were ascertained by polynomial fitting analysis. The unique characteristics of ceramic during laser drilling were also discussed. The results indicate that the ideal focal position to achieve minimum taper in laser drilling holes should be set above the surface of workpiece.