Laser-assisted machining (LAM) is a new method and actively researched for various difficult to machine materials. In LAM, machining is carried after prediction of material removal temperature (preheating temperature) for material with fixed cutting depth using a laser source. Among the various difficult-to-cut materials, Inconel 718, nickel-based super alloys, is difficult to machine due high strength at elevated temperature and low thermal conductivity. Studies on machining of Inconel 718 using a laser has been performed for various position of laser source to reveal the process benefits of Inconel 718 with fixed cutting depth. But there are no studies and results on prediction of heat affected depth for preheating temperature using laser assisted machining of Inconel 718 on various laser beam angle. So, in the present study, the effect of application of laser when applied at different angles is studied by two different methods-one with offset and other without offset. Finite element method is used to perform the simulations. This contribution brings a new novelty to the present research work on metal cutting domain using laser. The heat affected depth was also found and compared with depth obtained through experiments. And, the error percentage found for heat affected depth and preheating temperature is about 11%. The experimental results reveal that laser beam at an angle of 60°has maximum depth of cut, while minimum depth of cut is found at 90°. © 2017 Elsevier Ltd.