Electrochemistry and passivity of a Ti-15Mo-3Nb-3Al beta-titanium alloy in ambient temperature aqueous chloride solutions

Journal Article · Fri Oct 01 04:00:00 EDT 1993 · Journal of the Electrochemical Society; (United States)

DOI:https://doi.org/10.1149/1.2220909· OSTI ID:5784195

Kolman, D G; Scully, J R ^[1]

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1. Univ. of Virginia, Charlottesville, VA (United States). Dept. of Materials Science

To understand the effect of Mo-Nb additions on the electrochemical behavior of [beta]-titanium alloys in ambient temperature chloride solutions, characterization of the electrochemistry and passivity of a Ti-15Mo-3Al alloy ([beta]-21S) was undertaken. Both solution heat-treated (SHT) and peak-aged (PA) alloys exhibited passive anodic behavior in aerated and deaerated 0.6M NaCl, aerated and deaerated 0.6M NaCl adjusted to pH 1 with HCl, as well as aerated 5M HCl. X-ray photoelectron spectroscopy (XPS) performed after exposure to neutral 0.6M NaCl indicated that both PA and SHT [beta]-21S formed a predominantly TiO[sub 2] film. Auger electron spectroscopy (AES) and cathodic kinetics suggest that the Mo and Nb alloying additions are incorporated into the oxide in amounts less than that found in the alloys. The predominance of the passivating TiO[sub 2] may explain the similarity of the electrochemical behavior observed. However, in deaerated 5M HCl, all materials displayed active-passive behavior except for SHT [beta]-21S which was spontaneously passive. This result suggests that the presence of the [alpha]-phase is deleterious to the formation of a protective passive film on PA [beta]-21S in deaerated 5M HCl.

• OSTI ID: 5784195
• Journal Information: Journal of the Electrochemical Society; (United States), Journal Name: Journal of the Electrochemical Society; (United States) Vol. 140:10; ISSN 0013-4651; ISSN JESOAN
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360105 -- Metals & Alloys-- Corrosion & Erosion
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400400* -- Electrochemistry
ALKALI METAL COMPOUNDS
ALLOYS
ALUMINIUM ALLOYS
CHALCOGENIDES
CHEMISTRY
CHLORIDES
CHLORINE COMPOUNDS
COATINGS
DATA
ELECTROCHEMISTRY
EXPERIMENTAL DATA
HALIDES
HALOGEN COMPOUNDS
HYDROCHLORIC ACID
HYDROGEN COMPOUNDS
INFORMATION
INORGANIC ACIDS
METALLURGICAL EFFECTS
MOLYBDENUM ALLOYS
NIOBIUM ALLOYS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PASSIVATION
PROTECTIVE COATINGS
SODIUM CHLORIDES
SODIUM COMPOUNDS
TITANIUM ALLOYS
TITANIUM BASE ALLOYS
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS