This work focused on the basic relationships between tool
wear, surface integrity, and fatigue in end milling of Inconel
718. The key results may be summarized as follows:
x All the milled surfaces had roughness of less than 0.4 μm,
and the majority surface roughness less than 0.25 μm.
Higher tool wear produced less surface roughness.
x Thermal-induced white layers were not observed for the
concerned tool wear levels, which may be explained by
the improved cooling effectfrom the periodic tool/work
contact in milling compared to constant tool/work contact
in turning and grinding.
x The machined surface has been work-hardened due to the
dominant mechanical loading which can be seen by
relatively higher microhardness at milled surface.
x No fatigue occurred within four million cycles for all the
machined samples up to tool wear VB 0.2 mm. Tool wear
within a certain range doesn’t necessarily affect the
fatigue life.