摘要 |
FIELD: process engineering.SUBSTANCE: invention relates to production of cardio implants from titanium nickelid-based alloy with shape memory and superelasticity effects modified surface layer. Said implants are intended for long-term operation in cardiovascular system and feature corrosion resistance, biocompatibility and nontoxicity in biological media. Proposed method comprises making said cardio implant, chemical and electrochemical surface cleaning, surface cleaning by silicon ion flows produced by spraying silicon cathode in vacuum under conditions of high-dose ion implantation with fluence of (0.5÷6.0)×10cmto obtain modified 80-95 nm-thick surface layer. The latter consists of at least two sublayers. Outer 20-25 nm-thick sublayer contains oxygen, carbon, silicon and titanium at the following ratio of components, at.%: oxygen - 25-65, carbon - 1-5, silicon - 1-10, titanium making the rest. Mid 60-70 nm-thick sublayer contains oxygen, carbon, silicon, titanium and nickel at the following ratio of components, at.%: oxygen - 5-30, carbon - 1-5, silicon - 10-30, nickel - 1-50, titanium making the rest. Note here that maximum concentration of silicon is reached at 30-35 nm from the surface.EFFECT: modified surface layer features no apparent interface between sublayers.9 cl, 1 dwg |