CORROSION-RESISTANCE, MECHANICAL-PROPERTIES, CORROSION-FATIGUE STRENGTH AND CYTOCOMPATIBILITY OF NEW TI ALLOYS WITHOUT AL AND V

The effects of various metallic ions using various metallic powders on the relative growth ratio of fibroblasts L929 and osteoblasts MC3T3-E 1 cells were carried out. Ti, Zr, Sn, Nb and Ta had evidently no effec t on the relative growth ratios of cells. Otherwise, Al and V ions exh ibit cytotoxicity from a concentration of greater than or equal to 0.2 ppm. This Al effect on cells tend to be stronger in medium containing small quantity of V ions (less than or equal to 0.03 ppm). The new Ti -15%Zr-4%Nb-4%Ta-0.20%Pd alloy exhibited a higher corrosion resistance in physiological saline solution. The addition of 0.02%O and 0.05%N t o Ti-Zr alloy improved the mechanical properties at room temperature a nd corrosion fatigue strength. The relative growth ratios for the new Ti alloy plate and the alloy block extraction were unity. Further, the relative growth ratios were almost unity for the new Ti ahoy against apatite ceramic pins up to 10(5) wear cycles in Eagle's MEM solution. However, there was a sharp decrease for Ti-6%Al-4%V ELI alloy from 3 x 10(4) wear cycles as V ion was released during wear into the wear tes t solution since the pH of the Eagle's MEM increases with increasing w ear cycles. (C) 1998 Published by Elsevier Science Ltd. All rights res erved.