... CBN insert TNMA160408, Machining harden steel with HRC50-67, general gray cast iron with HB about 200, high hardness cast ... rev; Cutting deepth, about 0.2mm General gray cast iron with HB about 200, Cutting speed, 500-1000 m/min; ... 5; Cutting deepth, about 3.0mm High hardness cast iron with HRC50-64, Cutting speed, 50-100 m/min; Feed, ... 3 mm/rev, Cutting deepth, about 2.5mm CBN inserts for cutting tool