Multi objective optimization of water jet guided laser micro drilling on Inconel 718 using Taguchi Method

© 2020 The Authors. Published by Elsevier B.V.Water jet guided laser overcomes the adverse effects of conventional laser cutting and drilling processes, such as heat-affected-zone, spatter, burr formation, etc. Pressurized water in this novel process provides focusing, cooling and cleaning on the cut region, eliminating undesired side effects of the laser. The process is nowadays used in energy and aerospace industries for drilling micro cooling holes on turbine blades made of super alloys. However, more research on the process is required to understand the effects of the variables on cutting time and quality. Optimum conditions differ for various materials and geometries. In this study, a multi objective optimization is performed in terms of process time and taper of the micro holes drilled on Inconel 718, a commonly used material in gas turbines. Taguchi design of experiment and statistical analysis is used to perform the experiments and evaluate the results

A process modeling approach for micro drilling of aerospace alloys with a waterjet guided laser system

Laser drilling is a preferred method to make cooling holes on gas turbine parts. Although it is a fast process, there are some quality issues. Waterjet guided laser (WJGL) is a hybrid process, in which a laser beam is coupled with and guided through thin cylindrical waterjet. Pressurized water in this novel process provides focusing, cooling and cleaning of the machining zone, eliminating undesired side effects of the laser. The process can be conveniently used for micro drilling operations on aerospace jet engine parts. However, more research on the process is required to understand the effects of the variables on material removal rate. The drilling time varies for each material and geometry. Optimum parameters should be adjusted for each case. In this study, the material removal mechanism of WJGL is investigated and a holistic modeling approach is developed including the necessary parameters for drilling of different aerospace materials and hole geometries