IMPROVEMENT OF PHYSICAL AND CHEMICAL-PROPERTIES OF STEEL IMPLANTED WITH CR+, TI+, SI+ IONS

Low carbon steels (St3, St45) and a chromium doped steel (St40Cr) were implanted with 15-20 keV Ti+, Cr+ or co-implanted with (Ti + Si)+, (C r + Si)+ ions to a dose of 8 x 10(16) ions cm-2 . The composition of t he surface region was examined by RBS and nuclear resonance scattering techniques. These analyses showed a relationship between the implante d ion doses and the oxygen concentration in the layer. The hardness of the implanted surface grew with increasing ion dose. This effect is a ssociated with radiation damage and chemical compounds created in the surface regions of the ion-implanted steels. The corrosion properties of the steels were studied and the first results from electrochemical analysis of corrosion behaviour of samples in de-aerated borate buffer solution (pH = 6.5) are discussed.