An analysis of the machinability of ASTM grades 2 and 3 austempered ductile iron

► The chip thickness ratio calculated was r = 0.6, a lower value than most steels. ► The cutting tool worn faster when machining G2 than G3. ► Adhesion was stronger for G2, whereas abrasion was the dominant mechanism for G3. ► The specific cutting force, Kc1,1, decreases as the depth of cut increases. ► Comparison of the quantity Fc/ap showed that a positive geometry eases cutting.