Developmental Study of Artificial Joints with Anti-Wear Titanium Alloy

1.通过在高韧性基体金属表面晶化TiC微粒，使其与β-Ti合金相结合，研制出耐磨钛合金。这种合金不仅是一种耐磨材料，而且还能减少配合材料的磨损。耐磨表层采用PTA焊接工艺附着在β-Ti合金母材上.研究了耐磨钛合金与超高分子量聚乙烯（UHMWPE）的摩擦磨损性能。并与SUS-316、Ti-6Al-4V、β-Ti合金、氢氧化铝、氧化铝、钛合金氮化物等材料进行了比较。超高分子量聚乙烯对耐磨钛的磨损率略高于对氧化铝的磨损率，与对比铝的磨损率相当，低于对其他材料的磨损率.当在磨损试验中使用聚甲基丙烯酸甲酯（PMMA）代替UHMWPE以模拟骨水泥入口时，Ti-6Al-4V和β-Ti合金的磨损严重，介质颜色或变黑。而耐磨钛合金则没有这种现象，其磨损率与含铂的钛合金一样低.该耐磨钛合金可用于人工关节的滑动部件。如果表面粗糙度得到改善，聚合物的磨损率可以降低到小于氧化铝的情况。结果发现，耐磨钛不仅对超高分子量聚乙烯，而且对天然和人工软骨的高性能。

1. We developed the wear resistant titanium alloy by crystallizing the TiC fine particles on the surface of highly ductile base metal with beta-Ti alloy phase. This alloy is not only an anti-wear material but also decreases wear of mating materials. The wear resistant surface layr is attached on the beta-Ti alloy base metal by the PTA welding procedure.2. We measured friction and wear of wear resistant titanium alloy against ultra high molecular weight polyethylene (UHMWPE). The results were compared with those with SUS-316, Ti-6Al-4V, beta-Ti alloy, bitalium, almina and titanium alloy nitride. The wear rate of the UHMWPE against wear resistant titanium was slightly higher than that against alumia, as low as that against bitalium, and lower than those against the other materials.3. When polymethyl methacrylate (PMMA) was used in the wear test instead of UHMWPE in order to simulate the inlet of bone cement., the color or the medium turned to be black for the cases with Ti-6Al-4V and beta-Ti alloy due to severe abrasive wear. The wear resistant titanium alloy did not show such phenomenon and the wear rate was as low as the case with bitalium.4. The wear resistant titanium alloy can be used to the sliding parts in artificial joints. If the surface roughness is improved, the wear rate of polymers may decreases to be less than the case with alumina. It was found that the wear resistant titanium is high performance not only against UHMWPE but also against natural and artificial cartilage.