BORE CUTTING TOOL AND METHOD OF MAKING THE SAME

摘要

A bore cutting tool, particularly for cutting metal workpieces, includes a tool substrate and a tool coating on a surface of the tool substrate. The bore cutting tool comprises a plurality of pits in the surface of the tool substrate and wherein the tool coating extends over the pits such that the pit surface comprises the tool coating. In this way, the pit dimensions can be retained over prolonged tool life and the pits, with their coated surface, are particularly effective at retaining lubricant so that the thickness of a lubricant film can be increased as compared to a tool without the coated pits. In embodiments the pits are formed by laser etching and are present only on the cylindrical land. Average pit depth is suitably in the range 8 mum to 25 mum, average pit width and pit length is independently selected from 40 mum to 250 mum and average pit density is 20 to 30 pits/mm2.