적층가공된 티타늄 합금의 전기화학적 특성에 미치는 불산의 영향

• Published in: Corrosion science and technology Vol. 17; no. 4; pp. 166 - 175
• Main Authors: 김기태, K. T. Kim, 조현우, H. W. Cho, 장현영, H. Y. Chang, 김영식, Y. S. Kim
• Format: Journal Article
• Language: Korean
• Published: 한국부식방식학회 31.08.2018
• Subjects: Additive manufacture (3D printing); CP-Ti; Electrochemical properties; Hydrofluoric acid; Ti-6Al-4V; 금속공학; CP-Ti; Electrochemical properties; Ti-6Al-4V; Additive manufacture (3D printing); Hydrofluoric acid
• ISSN: 1598-6462; 2288-6524
• DOI: 10.14773/cst.2018.17.4.166

In this study, the electrochemical properties of CP-Ti (commercially pure titanium) and Ti-64 (Ti-6Al-4V) were evaluated and the effect of hydrofluoric acid on corrosion resistance and electrochemical properties was elucidated. Additive manufactured materials were made by DMT (Directed Metal Tooling) method. Samples were heat-treated for 1 hour at 760 °C and then air cooled. Surface morphologies were studied by optical microscope and SEM. Electrochemical properties were evaluated by anodic polarization method and AC-impedance measurement. The oxide film formed on the surface was analyzed using an XPS. The addition of HF led to an increase in the passive current density and critical current density and decreased the polarization resistance regardless of the alloys employed. Based on the composition of the oxide film, the compositional difference observed by the addition of HF was little, regardless of the nature of alloys. The Warburg impedance obtained by AC-impedance measurement indicates the dissolution of the constituents of CP-Ti and Ti-64 through a porous oxide film.