Basic study of ball end milling on hardened steel

This study deals with ball end milling with a (Al,Ti)N-coated tool on hardened steel. The cutting forces in ball end milling with a helical flute were obtained theoretically and experimentally not only for a flat surface, but also for an inclined work surface. They are agreed with each other. The influence of the cutting conditions on tool life is discussed: it changed from 200 to 1100 m, depending on the cutting conditions. For the cutting conditions of a large inclined angle of the work-piece surface and a large feed rate, a long tool life was obtained. The causes of reduced tool life changed, depending on the cutting conditions.