Structure and wear resistance of 20X13 steel ion-implanted with nitrogen at a high beam-current density

X-ray diffraction and optical and electron microscopy were used to analyze microstructural variations in the surface layers of 20X13 steel after low-energy, high current-density ion implantation. These data show that nitrogen implantation produces solid solutions and precipitates of new phases in surface layers which are several mu m thick. Tribological measurements made on steel blocks in a block-on-ring tester show that implantation increases wear resistance and reduces the friction coefficient on the surface. The phases formed are controlled by the temperature of implantation and the ion fluence. Higher implantation temperatures, which induce a more effective hardening of surfaces, yield a heterogeneous structure which is unsuitable for some tribological applications and is less corrosion-resistant than the homogeneous structure observed at lower temperatures. (C) 1997 Published by Elsevier Science S.A.