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

•A process input flowchart is presented for a holistic material removal model.•Significant process parameters affecting the material removal are determined.•The methods are presented to determine the in-process unknown variables.•The model can estimate the process time and/or hole depth. 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.