인공고관절용 스테인리스강 316L에 증착된 다이아몬드상 카본 필름의 전기화학적 특성에 관한 연구

Diamond-like carbon (DLC) films have several advantages in applications such as high hardness, chemical inertness, low friction and electrical insulation. Furthermore, DLC-coated STS 316L films have been reported to have a good biocompatibility, such as the absence of inflammatory response. Thus, corrosion resistance is the first consideration for the biomaterials to be used in the body. DLC films have been deposited onto substrates of STS 316L for artificial hip joints using r.f. PACVD with C₆H₆ and mixture of C₆H₆ and SiH₄ as the process gases. Three kinds of DLC-coated films were prepared as a function of diverse bias voltage and Si incorporation. Corrosion behavior of DLC films was investigated by electrochemical techniques (potentiodynamic polarization test and electrochemical impedance spectroscopy) and surface analysis (atomic force microscopy and scanning electron microscopy). The electrolyte used in this test was a 0.89% NaCL solution of pH 7.4 at temperature 37^oC. Electrochemical measurements showed that DLC films with higher bias voltage and Si incorporation could improve corrosion resistance in the simulated body fluid environment.