纳米非晶金刚石薄膜对钴铬合金表面腐蚀性能的影响

Influence of nanometer amorphous diamond film on the corrosion resistance of the surface of dental Co-Cr alloys

目的:探索纳米非晶金刚石薄膜对牙用钴铬合金表面腐蚀性能的影响。方法:将硬质钴铬合金锭铸造成直径20mm、长15cm的圆棒,再将圆棒加工成直径15mm、厚2mm的圆片试件24个,随机分成两组,一组试件表面镀纳米非晶金刚石薄膜,为实验组;另一组为对照组表面未作任何处理。将两组试件分别浸于人工唾液中,采用电化学方法测试其腐蚀性,电镜下观察实验后试件表面形态。结果:实验组自腐蚀电位(Ecorr)、过钝化电位(Etp)与对照组比较,存在非常显著性差异(P<0.01);电镜显示,实验组试件表面存在少量腐蚀坑,对照组试件表面可见大量密集的腐蚀坑。结论:纳米非晶金刚石薄膜可以显著提高牙用钴铬合金的耐腐蚀性能。

Objective To study the influence of the nanometer amorphous diamond film on the corrosion resistance of the surface of dental Co-Cr alloys. Methods We used plenty of Co-Cr alloys ingots to cast a cylinder with size of diameter 20mm and length 15mm. Then the cylinder was machined into 24 disks with size of diameter 15mm and depth 2mm. These disks were divided into two groups.one group is experiment group which was plated with nanometer amorphous diamond film on surface, the other group is control group.The disks of two groups were immersed into artificial saliva and then subjected to test their corrosion resistance using the electrochemical method. When the experiments were over, the surfaces of the disks were examined with electron microscope. Results There was significant difference between the experiment and control groups on corrosion potential and transpassive potentiat.Using electron microscope, we could find more and much intensive corrosive pits on the surface of control groups disks than those on the surface of experiment groups disks. Conclusion The nanometer amorphous diamond film can significantly improve the corrosion resistance of the surface of dental Co-Cr alloys.