Fabrication and characterization of micro-channels on Al2O3/TiC ceramic produced by nanosecond laser

In this paper, a nanosecond laser with wavelength of 1064 nm is used to fabricate micro-channels on Al2O3/TiC ceramic, the influence of laser process parameters (voltage, scanning speed, frequency and the number of overscans) on surface quality and dimensions of micro-channels is investigated. The surface morphology, channel width and depth, and surface composition in ablated zone are measured by scanning electron microscope (SEM), optical profiler, energy dispersive X-ray (EDX) and X-ray diffraction (XRD). Results show that the heat-affected zone is formed surrounding the micro-channels with the oxidation reactions, and the surface morphologies and dimensions of micro-channels are strongly dependent on the laser process parameters. The high voltage, low scanning speed, high frequency and high number of overscans are prone to create large channel width and depth within a certain range induced by higher energy accumulation, however, excessive energy accumulation may lead to the reduced channel width and depth. Based on the experimental results, the optimal laser process parameters for better surface quality of micro-channels are obtained, accordingly, the desired micro-channels with the width of about 50 mu m and depth of about 43 mu m are fabricated.