LBM of aluminum alloy: towards a control of material removal and roughness

Abstract

Achieving the maximum material removal rate (MRRmax) is not always desired in machining especially during laser milling. Actual volume of the material removed during laser beam machining (LBM) is not always precisely equal to the designed volume. Dimensional accuracy of the laser milled feature requires the controlled layer of the substrate removal after each scanning cycle so that the cumulative material removal after full length of canning cycle conforms to the designed depth or geometry. In this research, laser milling of aluminum alloy has been carried out. Percentage of material removal rate (MRR%) and the roughness of the machined surface (SR) are taken as the response indicators. Optimal parametric combinations resulting in MRR% close to 100% with minimum SR have been pursued. Strength of the effects of five significant variables (in terms of one-way, square, and two-way interactions) is also identified. Furthermore, mathematical models are developed to predict the machining responses prior to proceed for actual machining. The research outcomes may be utilized to perform laser milling of AA 2024 (aluminum alloy used in various fields including aerospace industry) with precise control over MRR which ultimately will strengthen the dimensional accuracy of the machined profiles.