Experimental Investigation of Varying Laser Pass on Micro-channel Characteristics of Thick PMMA by Laser Transmission Micro-machining

Abstract Depth of fabrication is an essential characteristic of micro-channels. The laser beam machining process is one of the most suitable processes to fabricate micro-channels. This process has an excellent potential for the fabrication of microfluidic devices which are instrumental for various biomedical applications such as electrophoresis, chromatography, blood protein studies, DNA analysis, etc. In this research work, an attempt has been made to fabricate micro-channels on a thick Polymethyl methacrylate (PMMA) plate at submerged condition by utilizing laser transmission micro-machining process. The laser transmission micromachining operation is conducted here at submerged condition to reduce the adverse thermal effect during machining. Nanosecond pulsed Nd: YAG laser with wavelength in near infrared region has been used here. The depth of micro-channel and heat affected zone (HAZ) width has been taken into account as machining responses. Total 3 sets of experiments which contain 31 experiments in each set have been conducted for three different laser beam pass with the aid of response surface methodology (RSM). The effects of varying laser beam pass on the depth and HAZ width has been studied.