CFRP (Carbon fiber reinforced plastic) has been widely used in different industries such as aerospace, automobile, sports and medical. Laser processing of CFRP has a great potential for industrial applications. In this paper researched the micro cutting and drilling of CFRP with 0.5 mm thickness using 1064 nm ytterbium nanosecond pulsed fiber laser. It also investigated machining characteristics of micro cutting and drilling according to laser power, frequency, scan speed and number of scan (or irradiation). Complete cutting and through-hole drilling were achieved with low frequency when the laser power was low and with low and middle frequency when the laser power increased. However, those were not achieved a frequency of 100 kHz. The cutting width increased when the power increased and decreased when the frequency and the scan speed increased. The hole size increased when the power and the number of irradiation increased and decreased when the frequency increased. In the case of micro hole array, the hole was blocked during the next hole machining when the hole spacing was narrow. The resin was melted by the heat thus blocking the pre-drilled hole. We devised the laser scan method, and the micro hole array with narrow hole spacing was fabricated successfully.

The mechanical drilling of micro holes is considered a difficult endeavor, due to the high hardness and brittleness of alumina plates found during the drilling process. In this work, an alumina plate with a 4mm thickness is drilled with the use of a continuous-wave Nd:YAG fiber laser. As can be seen, there is minimum required power density to ablate the alumina plate. As shown in this study, the hole diameter and straightness are not constant with the hole depth recorded, which is presumably due to the recondensation of vaporized alumina, and the characteristics of irregular laser radiation. The oxygen pressure, power density, focal position, and laser on time (duration) are chosen as the control parameters. To understand the influence of control parameters, the orthogonal arrays table in Taguchi method is applied, and the micro holes are evaluated based on the use of geometrical factors. Through the review of a sensitivity and interaction analysis, the appropriate duration and oxygen pressure are identified as the major parameters governing the geometrical quality of drilled holes in this study.