Study of phenomena responsible for part distortions when turning thin Inconel 718 workpieces

•A thorough in-situ experimental procedure to measure geometrical errors is presented.•Geometrical errors due to cutting forces and machining induced residual stresses are separated.•In the studied case, the impact of subsurface residual stresses on the total geometrical error is not negligible.•Tool wear dramatically increases the distortions linked to cutting forces and subsurface residual stresses.•The proportion of total errors linked to machining induced residual stresses increase with tool wear.