Experimental study on realizing blind micro-grooves on the surface of an aluminum sheet using two nanosecond lasers

Although aluminum processing with lasers has become popular in industrial applications, machining some blind grooves or blind holes with a required size in aluminum sheets is also a difficult task for laser technicians. In this paper, blind grooves with the depth of about 0.1 mm and the width of less than 0.1 mm on a 0.24 mm thick aluminum sheet have been realized by using two kinds of nanosecond Q-switched lasers without burning the coating polymer layer. The effects of the laser wavelength, average power, and scanning speed on laser processing have been investigated in detail. The groove machining of aluminum sheets has been carried out at different laser power and machining speeds by use of two Q-switched lasers with the wavelengths of 532 nm and 355 nm. The experiment result shows that the faster the scanning speed, the better the processing efficiency. And the status of blind grooves processed by a 355 nm laser is cleaner and smarter. In summary, the optimal laser parameters for processing grooves on the aluminum surface are the peak power density of 2.27×108 W/cm² with the scanning speed of 0.1 mm/s for a 355 nm nanosecond laser. The results of our study might be of great importance as a reference for processing blind grooves on aluminum sheets in some industrial applications.