不锈钢根管锉镀覆TiN、ZrN膜的沉积工艺与性能研究

目的通过在不锈钢根管锉表面镀覆Ti N、Zr N薄膜,以提高其切削性能。方法采用磁控溅射技术,调整沉积时间、基片偏压、占空比等工艺参数在不锈钢根管锉上分别沉积Ti N、Zr N薄膜。对Ti N、Zr N膜层进行SEM断面分析、XRD相组成分析、表面硬度测试、膜层附着力测试,考查了Ti N、Zr N薄膜的厚度、相组成、硬度以及附着力。通过对镀膜后的根管锉进行电化学腐蚀试验、模拟临床切削试验,分析了镀膜后根管锉的耐蚀性和切削性能。结果随着工艺参数的变化,Ti N、ZrN薄膜的厚度、相结构以及硬度均显示了规律性的变化。镀覆Ti N、Zr N薄膜的不锈钢根管锉的自腐蚀电流密度相对于未镀膜的根管锉均明显降低。确定了Ti N膜层和Zr N膜层的优化沉积工艺分别为沉积时间1 h、负偏压100 V、占空比60%和沉积时间1h、负偏压150V、占空比60%。优化工艺下镀膜的不锈钢根管锉的切削数量和切削效率显著提高。结论和未镀膜不锈钢根管锉相比,镀覆Ti N、ZrN薄膜的不锈钢根管锉的表面硬度、耐蚀性能均有显著提高。最优工艺下制备的镀覆Ti N、Zr N薄膜的不锈钢根管锉兼具切削数量、切削效率以及切削稳定性等方面的综合优势,和未镀膜不锈钢根管锉相比,切削效率提高60%～75%,切削树脂模拟根管数量达到1.7～2倍,实现了切削性能的显著提升。

Deposition Process and Properties of TiN and ZrN Films Coated on Stainless Steel Root Canal Files

The work aims to improve cutting performance of stainless steel root files by coating TiN and ZrN films on the surface. TiN and ZrN thin films were deposited on stainless steel root canal files by magnetron sputtering with adjusting deposition time, substrate bias and duty cycle. The thickness, phase composition, hardness and adhesion of the TiN and ZrN films were examined by SEM, XRD and surface hardness and adhesion tests. The corrosion resistance and the cutting performance of the coated root canal files were analyzed by the electrochemical corrosion test and the simulated clinical cutting test. The thickness, phase structure and hardness of the TiN and ZrN films changed with the deposition process parameters. The corrosion current density of stainless steel root canal files coated with TiN and ZrN films decreased significantly compared with that of the uncoated ones. The optimized deposition processes of TiN and ZrN films were determined to be: deposition time of 1 h, negative bias of 100 V and duty cycle of 60% and 1 h, negative bias of 150 V and duty cycle of 60% respectively. The cutting quantity and efficiency of stainless steel root canal files coated with the optimized process were significantly improved. Compared with the uncoated ones, the stainless steel root canal files coated with TiN and ZrN films improve significantly the surface hardness and corrosion resistance. The stainless steel root canal files optimally coated with TiN and ZrN thin films exhibit the multiple advantages of cutting quantity, cutting efficiency and cutting stability. The cutting efficiency is increased by 60%~75%, and the number of the cut resin root canals is 1.7~2 times in comparison with the uncoated stainless steel root canal files. The remarkable improvements in cutting performance are achieved.