Experimental and Modeling Study of Liquid-Assisted—Laser Beam Micromachining of Smart Ceramic Materials

Abstract

Smart ceramic materials are next generation materials with the inherent intelligence to adapt to change in the external environment. These materials are destined to play an essential role in several critical engineering applications. Machining these materials using traditional machining processes is a challenge. The laser beam micromachining (LBMM) process has the potential to machine such smart materials. However, laser machining when performed in air induces high thermal stress on the surface, often leading to crack formation, recast and re-deposition of ablated material, and large heat-affected zones (HAZ). Performing laser beam machining in the presence of a liquid medium could potentially resolve these issues. This research investigates the possibility of using a Liquid Assisted-Laser Beam Micromachining (LA-LBMM) process for micromachining smart ceramic materials. Experimental studies are performed to compare the machining quality of laser beam machining process in air and in a liquid medium. The study reveals that the presence of liquid medium helps in controlling the heat-affected zone and the taper angle of the cavity drilled, thereby enhancing the machining quality. Analytical modeling is developed for the prediction of HAZ and cavity diameter both in air and underwater conditions, and the model is capable of predicting the experimental results to within 10% error.

Efficient Water-Assisted Glass Cutting with 355 nm Picosecond Laser Pulses

“…Additionally, multiple studies have reported the improved extraction of ablation products, reduced plasma shielding, and the generation of high-pressure mechanical shockwaves, which further contributed to material removing rates [ 22 , 23 ]. Additionally, improved machining quality was also observed: reduced heat-affected zones (HAZs), micro-cracks, and the re-deposition and recast of ablative debris [ 21 , 24 , 25 , 26 , 27 ].…”

Molecular Dynamics Simulation Study of Liquid-Assisted Laser Beam Micromachining Process

“…Performing the LBMM process in a liquid medium is a potential approach to overcome these limitations of the LBMM process [9]. The process known as Liquid-Assisted Laser Beam Micromachining (LA-LBMM) is capable of micromachining materials with features ranging from 100 to 500 µm with reduced thermal damage, with relatively narrow kerf width, and a reduced re-deposition of debris [10,11].…”

“…The LA-LBMM process can be performed both in static mode (still water) and dynamic mode (flowing water) [13]. Studies have reported that the liquid layer helps in cooling the workpiece, which minimizes the HAZ formation during the machining process [10,11,13,14]. During static mode, which minimizes the HAZ formation during the machining process [10,11,13,14].…”

“…Studies have reported that the liquid layer helps in cooling the workpiece, which minimizes the HAZ formation during the machining process [10,11,13,14]. During static mode, which minimizes the HAZ formation during the machining process [10,11,13,14]. During static mode, the molten debris re-deposit on the machined area, which piles up in the center and is removed by subsequent laser energy [13].…”