Improving Tool Performance in Turning Hard Stainless Steels

An innovative technology is described for improving tool performance in external turning of stainless steels: the application of new coatings to VK8 hard alloy tools. Tool performance is determined from the life of the replaceable standard cutting inserts. The working life of the inserts ends when the wear at the rear face reaches the limiting permissible value (0.5 mm). Such coatings may increase the working life of VK8 alloy tools as much as threefold, without impairing the productivity or the surface quality of the workpiece.