化學成份對牙科用Ni-Cr-Mo合金耐蝕性質之影響

Compositional influence on the corrosion resistance of ni-cr-mo dental alloys

10.6376/JCCE.200206.0065

林茂欽(Mau-Chin Lin)；黃何雄(Her-Hsiung Huang)

成份 ； 腐蝕 ； 鈍化膜 ； 孔蝕 ； Ni-Cr-Mo合金 ； composition ； corrosion ； passive film ； pitting ； Ni-Cr-Mo alloy

防蝕工程

16卷2期（2002 / 06 / 01）

65 - 74

繁體中文

The objective of this investigation was to study the compositional influence on the corrosion behavior of Ni-Cr-Mo dental casting alloys in acidic artificial saliva. Cyclic potentiodynamic and potentiostatic tests were used to evaluate the corrosion behavior of different Ni-Cr-Mo dental casting alloys in deaerated artificial saliva with pH 5 at 37℃.Optical microscope observations were carried out after the cyclic potentiodynamic tests. Surface chemical analyses were characterized by X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) after potentiostatic tests. The results of corrosion tests showed that the corrosion resistance of Ni-Cr-Mo casting alloys was associated with the formation of passive film, containing Ni(OH)2,NiO,Cr2O3 and MoO3,on the surface. The Ni-Cr-Mo alloy with higher Cr(≈21%)and Mo(≈8%)contents had much larger passive region in the polarization curve and was immune to pitting corrosion, which was due to the presence of high Cr(maximum≈31-35%)and Mo(maximum≈12%)contents in the surface passive film. The presence of Ti lower than 4% in the Ni-Cr-Mo casting alloy had no effect on the corrosion resistance. A pitting resistance equivalent (PRE) of about 49 could provide the Ni-Cr-Mo alloy with a good pitting corrosion resistance.

The objective of this investigation was to study the compositional influence on the corrosion behavior of Ni-Cr-Mo dental casting alloys in acidic artificial saliva. Cyclic potentiodynamic and potentiostatic tests were used to evaluate the corrosion behavior of different Ni-Cr-Mo dental casting alloys in deaerated artificial saliva with pH 5 at 37℃.Optical microscope observations were carried out after the cyclic potentiodynamic tests. Surface chemical analyses were characterized by X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) after potentiostatic tests. The results of corrosion tests showed that the corrosion resistance of Ni-Cr-Mo casting alloys was associated with the formation of passive film, containing Ni(OH)2,NiO,Cr2O3 and MoO3,on the surface. The Ni-Cr-Mo alloy with higher Cr(≈21%)and Mo(≈8%)contents had much larger passive region in the polarization curve and was immune to pitting corrosion, which was due to the presence of high Cr(maximum≈31-35%)and Mo(maximum≈12%)contents in the surface passive film. The presence of Ti lower than 4% in the Ni-Cr-Mo casting alloy had no effect on the corrosion resistance. A pitting resistance equivalent (PRE) of about 49 could provide the Ni-Cr-Mo alloy with a good pitting corrosion resistance.