Influence of cutting parameters on work hardening behavior of surface layer during turning superalloy Inconel 718

The use of superalloy Inconel 718 is increasing inmost of sophisticated applications such as aircraft and rocket engines. However, the high work hardening behavior of Inconel 718 has not been studied sufficiently yet. In the present work, an experimental work was made to study the relationship between work hardening and cutting parameters (cutting speed and feed rate) in turning Inconel 718. Depths of work hardening and degree of work hardening (DWH) at different depths beneath the machined surfaces were investigated to determine and understand the integrity of machined surfaces. It is observed that there was no significant difference with work hardening characteristics in this experiment to consider the error of measurement. The parameters (v = 50 m/min, f = 0.2 mm/r) may be better than others. An empirical model based on Meyer's index with a view was utilized to understand the characteristics of machining-affected layers. From the obtained data, the work hardening can be better understood and controlled, which can be used to enhance the machinability and surface integrity characteristics of superalloy Inconel 718.