... TNMA160408, Machining harden steel with HRC50-67, general gray cast iron with HB about 200, high hardness cast iron with HRC50-64 and so on ... mm/rev; Cutting deepth, about 0.2mm General gray cast iron with HB about 200, Cutting speed, 500-1000 m/min; Feed ... -0.5; Cutting deepth, about 3.0mm High hardness cast iron with HRC50-64, Cutting speed, 50-100 m/min; Feed, 0 ...