Cutting tools hardening and sharpening by fast argon and nitrogen atoms

Abstract

A reamer made of AISI M2 high-speed steel was heated by ions accelerated from the plasma by a bias voltage applied to it and kept at 500°C for 120 min. Microhardness of the reamer surface increased by 1.75 times and the nitride layer thickness reached 130 μm. Nevertheless, radii of the cutting edges increased by 5 times up to ~ 40 μm, which made the tool blunt. Another reamer was heated by a converging beam of fast atoms produced by an immersed in the same plasma concave grid under a negative voltage of 5 kV. Due to uniform removal of the reamer material by the beam, the radii of cutting edges decreased from the initial value ~ 8 μm down to ~ 6 μm.