Modification of hard alloy by the action of high power ion beams

Phase composition, sizes of coherent scattering regions, hardness and friction coefficient of WC-TiC-Co hard alloy and “(Ti,Cr)N coating-on-alloy” system treated by high power ion beams (HPIB) are studied. HPIB treatment was carried out with power densities from 4 to 16 J/cm². The effect of HPIB pretreatment (4 J/cm²) before deposition procedure was studied. HPIB action with energy densities of 8-16 J/cm² on hard alloy results in partial fusion of tungsten and titanium carbides. The hardness of surface layer increases by two times and wear resistance improves. HPIB action on “coating-on-alloy” system leads to coarsening of (Ti,Cr)N crystallites, partial decomposition of (Ti,Cr)N and precipitation of chromium phase. Preliminary HPIB treatment (4 J/cm²) followed by HPIB impact (16 J/cm²) provides best effect on wear-resistance of (Ti,Cr)N solid solution on hard alloy.