In-situ investigation of the evolution of microstructure and texture during load reversal of commercially pure titanium using synchrotron X-ray diffraction

This paper presents the results of a defect structure investigation in commercially pure titanium alloy after hydrogen charging in a gaseous atmosphere at the temperature of 873 K up to the concentration of 5.1 at. %. Structure of samples was studied by positron lifetime, Doppler broadening and X-ray diffraction spectrometry. Several processes, corresponding to the different ranges of hydrogen concentrations were revealed. It was shown that hydrogen, penetrating in the material, expands its crystal lattice, initiates formation of vacancy-like defects of different dimensions and reacts with the last ones, forming the defect-hydrogen complexes.

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Oxidation kinetics of commercially pure titanium

Matéria (Rio de Janeiro) ◽

10.1590/s1517-70762007000300014 ◽

2007 ◽

Vol 12 (3) ◽

pp. 525-531 ◽

Cited By ~ 59

Author(s):

E. Gemelli ◽

N.H.A. Camargo

Keyword(s):

Oxidation Kinetics ◽

Room Temperature ◽

Thermal Analyses ◽

Pure Titanium ◽

Thermal Characterization ◽

Commercially Pure Titanium ◽

X Ray Diffraction ◽

X Ray ◽

Temperature Range ◽

Commercially Pure

The aim of this work was to perform thermal characterization of commercially pure titanium in dry air to determine its oxidation kinetics and the structure of the oxide. The oxidation kinetics were determined thermogravimetrically under isothermal conditions in the temperature range 300 to 750 ºC for 48 hours and the structure of the oxides was determined by differential thermal analyses and X-ray diffraction in the temperature range room temperature - 1000ºC. The oxidation rate of titanium increased with increase in temperature. It was high in the initial stages of oxidation and then decreased rapidly with time, especially up to 600 ºC. The kinetic laws varied between inverse logarithmic at the lower temperatures (300 and 400 ºC) and parabolic at the higher temperatures (650, 700 and 750 ºC). Evidences from X-ray diffraction and differential thermal analyses data revealed that the passive oxide film formed at room temperature crystallized into anatase at about 276 ºC. The crystallized oxide formed in the range 276 - 457 ºC consisted of anatase, in the range 457 - 718 ºC consisted of anatase and rutile sublayers, and at temperatures beyond 718 ºC consisted of a layer of pure rutile. Scanning electron microscopy observations reveled that the oxidized surfaces were crack-free and the surface roughness increased steadily with oxidation temperature.

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Bioactive Porous Film Produced on Titanium Substrate by Micro-Arc Oxidation

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.1201 ◽

2008 ◽

Vol 368-372 ◽

pp. 1201-1202

Author(s):

Q. Ma ◽

Y.J. Wang ◽

Cheng Yun Ning ◽

Hai Mei Cheng ◽

Zhao Yi Yin

Keyword(s):

Pure Titanium ◽

Titanium Substrate ◽

Disodium Salt ◽

Commercially Pure Titanium ◽

X Ray Diffraction ◽

Electrolytic Solution ◽

Glycerol Phosphate ◽

X Ray ◽

Commercially Pure ◽

Micro Arc Oxidation

Porous bioactive thin film on commercially pure titanium substrate was prepared by micro-arc oxidation (MAO) in electrolytic solution, which contained calcium acetate, β-glycerol phosphate disodium salt pentahydrate (β-GP) and lanthanum nitrate. The phases and microstructure of the bioactive films were examined by X-ray diffraction, scanning electron microscopy with energy dispersive X-ray spectrometer and electron probe microanalysis. The results showed that: (1) porous bioactive films with about 10μm were formed on titanium substrate by MAO; (2) phases of the thin films were hydroxyapatite, anatase and rutile; (3) elements of Ca, P, and Ti of films were identified by EDS.

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EFFECT OF THERMAL OXIDATION ON THE CORROSION RESISTANCE OF CP-TI

Acta Metallurgica Slovaca ◽

10.12776/ams.v23i2.927 ◽

2017 ◽

Vol 23 (2) ◽

pp. 135

Author(s):

Shijing Lu ◽

Kunxia Wei ◽

Yan Wang ◽

Jing Hu

Keyword(s):

Corrosion Resistance ◽

Thermal Oxidation ◽

Pure Titanium ◽

Immersion Test ◽

Commercially Pure Titanium ◽

X Ray Diffraction ◽

X Ray ◽

Commercially Pure ◽

Different Temperatures ◽

Cp Ti

Commercially pure titanium (CP-Ti) was subjected to thermal oxidation at different temperatures and times for determining the optimum oxidation conditions to obtain the optimum corrosion resistance. The phase constituents of the samples were determined by X-ray diffraction (XRD), the morphology of the surface was observed by SEM, and the corrosion behavior was investigated using immersion test by exposing the samples in HCl solutions with a concentration of 37%. The results showed that Rutile TiO2 layer was formed on the surface of CP-Ti after thermal oxidation and the thickness of the TiO2 layer increased with the treating temperature. Meanwhile, It was found that the optimum corrosion resistance to HCl was obtained while oxidizing at 700℃ for 330min～500min.

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Investigation of Commercially Pure Titanium Structure during Accumulation and Release of Hydrogen by Means of Positron Lifetime and Electrical Resistivity Measurements

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.880.93 ◽

2014 ◽

Vol 880 ◽

pp. 93-100 ◽

Cited By ~ 20

Author(s):

Yuriy S. Bordulev ◽

Roman S. Laptev ◽

Viktor N. Kudiiarov ◽

Andrey M. Lider

Keyword(s):

Electrical Resistivity ◽

Positron Lifetime ◽

Vacuum Annealing ◽

Pure Titanium ◽

Commercially Pure Titanium ◽

X Ray Diffraction ◽

X Ray ◽

Resistivity Measurements ◽

Commercially Pure ◽

Titanium Structure

In this work the goal was to study the behavior of titanium-hydrogen system with hydrogen concentration of 1 wt. % at high temperature vacuum annealing by means of positron lifetime (PL) spectroscopy and electrical resistivity measurements. The range of hydrogen concentrations under investigation requires the γ phase formation. The study is related with the X-ray diffraction (XRD) and thermal desorption spectra (TDS) analysis. The registered positron lifetime spectra were analyzed by multiexponential decomposition into two components. Correlation of changes of the parameters of the PL spectrum and the electrical resistivity is revealed in this paper.

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