骨用镁合金表面Ti-Cu涂层的腐蚀行为

背景：镁合金作为骨折内固定材料具有力学性能与骨相近、生物相容性好和可降解等突出优点,但其在体液中降解速度过快,成为其临床应用的瓶颈,因此综合利用表面处理提高其耐蚀性能具有重要意义。目的：综合运用磁控溅射技术和碱热处理技术在镁合金表面制备兼具耐蚀性能和生物活性的涂层。方法：首先采用熔炼技术制备Mg-Zn-Mn合金,利用磁控溅射技术在材料表面制备致密涂层,然后利用碱性溶液对表面涂层进行处理,利用模拟体液浸泡实验研究涂层的腐蚀行为,通过表面产物中钙和磷的含量推测涂层的生物活性。结果与结论：经磁控溅射和碱热处理技术在镁合金表面制备兼具耐蚀性能和生物活性的涂层;经模拟体液浸泡24和168 h后涂层表面沉积含Ca,P产物,Ca/P比分别为1.54和2.11,接近类骨磷酸盐Ca/P比,涂层表面的浸泡24 h形成5-10 μm点腐蚀,随着浸泡时间增加点腐蚀逐渐长大,浸泡168 h后点腐蚀增加为100-800 μm。

Corrosion behavior of Ti-Cu coating on the surface of bone magnesium alloy

BACKGROUND:Magnesium alloy as a fracture fixation material has mechanical properties similar to the bone, good biocompatibility and biodegradability, but its rapid degradation rate in body fluids becomes a clinical bottleneck. Therefore, the use of surface treatments to improve its corrosion resistance is important.OBJECTIVE:To use magnetron sputtering technology and alkali heat treatment technology in the preparation of coating characterized as both corrosion resistance and biological activity.METHODS:First, we prepared Mg-Zn-Mn alloy using the smelting technology, and prepared a dense coating on the alloy surface by the magnetron sputtering technique. Then, we processed the coating surface using an alkaline solution, and studied the corrosion behavior of the coating by use of simulated body fluid experiments. We speculated the biological activity of the coating by measuring the content of calcium and phosphorus from the surface products.RESULTS AND CONCLUSION:We prepared the coating, which had both corrosion resistance and biological activity, on the surface of magnesium alloy by use of magnetron sputtering and alkali heat treatment technology. After soaking in the simulated body fluid for 24 hours and 168 hours, the deposition of the coating surface contained Ca, P products. Ca/P ratios were 1.54 and 2.11, respectively, closed to the bone-phosphate Ca/P ratio. The coating surface formed 5-10 μm pitting after 24 hours of immersion, and the pitting grew up with the immersion time. The pitting was enlarged to 100-800 μm after 168 hours.