Study on Machinability of 35CrMnSiA Steel in Hard Turning Process

35CrMnSiA, is a kind of important engineering materials that used widely in modern manufacturing fields. The machinability of 35CrMnSiA Steel with hardness of HRc40+/-2 in high speed turning process was studied in this paper. It is concluded that, when high speed turning of this ultra-high strength alloy steel, the chief wear mode of ceramics is the crater on rake faces; the interaction of depth of cut and feed rate is one of statistic significant effects on cutting force; the interaction of cutting velocity of cut and feed rate is one of statistic significant effects on surface roughness Ra; besides, the empirical formula of average cutting temperature, cutting forces, surface roughness Ra, was established.