Surface treatment of steel by short pulsed injection of high-power ion beam

A hydrogen-high power and short pulsed ion beam (PPIB) with ion energy of 1 60 keV, ion beam current density of 500 A/cm(2) and pulse duration (FWHM) o f 65 ns was injected into a high-speed tool steel (SKH51), producing an aus tenitic phase in MI-sized polycrystals on the surface layer of target. The average crystal size in the austenitic phase was estimated to be 40 nm, whi ch is 1/170 of crystal size before the PPIB injection. The heat affected de pth is estimated to be approrrimately 1.0 mum from the surface that is in g ood agreement with the ion range calculated by TRIM code. (C) 2001 Elsevier Science B.V. All rights reserved.