Corrosion Behavior Of Ti Research Articles

Metal-Fluoride Complex Stability Constant in Acid Solution as an Indicator to Identify the Corrosion Behavior of Metal Cations on Titanium

The Ti was immersed in 0.058 mol/L NaF containing 1.68 mol/L H2SO4 solution with different metal cations (Ca2+, Cu2+, Fe2+, Mg2+, Mn2+, Ni2+, Zn2+, Al3+, and Fe3+) for 7 d to identify the role of metal cations on corrosion behavior of titanium. To elucidate the role of metal cations on the corrosion behavior of Ti in acid solution, the standard electrode potential, E0, hardness of metal cations, X, and metal-fluoride complex stability constant, Kn, were chosen as the potential indicator. It is found that the mass loss fraction obtained from the immersion tests as a function of the metal-fluoride complex stability constant, Kn, has the highest correlation coefficient (0.92). The metal cations (Al3+ and Fe3+) with higher stability constant of the metal-fluoride complex in acid solution, (Kn > 3.27), show corrosion inhibition effect on Ti in acid solution. The Kn could be a suitable indicator to understand the role of metal cations on the Ti corrosion mechanism.

Corrosion behavior of Ti−6Al−4V alloy fabricated by selective laser melting in simulated spent fuel reprocessing environment

Corrosion behavior of Ti−6Al−4V alloy fabricated by selective laser melting in simulated spent fuel reprocessing environment

Influence of Candida albicans-Streptococcus mutans cross-border interactions on the corrosion behaviour of Ti and Ti-Zr in artificial saliva

This study evaluated and compared the corrosion effects of Streptococcus mutans (S. mutans), Candida albicans (C. albicans), and their mixture on implant materials Ti and Ti-Zr. Corrosion tests were conducted in simulated artificial saliva. The results showed differences in biofilm structure, corrosion behavior, and mechanisms between single and mixed bacteria. The cross-kingdom interaction between S. mutans and C. albicans enhanced biofilm maturity and acidity, providing necessary conditions for pitting corrosion. C. albicans played a dominant role in the interaction between C. albicans and S. mutans. Furthermore, Ti-Zr exhibited higher corrosion resistance compared to Ti.

Assessment of in-vivo corrosion of Ti and CoCrMo joint implants by electrochemical measurements in human synovial liquids

Understanding the corrosion behavior of biomedical materials in the human body is an essential step for the development of improved materials and clinical procedures in arthroplasty. In this work, the corrosion behavior of Ti and CoCrMo alloys in human synovial fluids directly extracted from patients was investigated through an electrochemical experimental protocol, including open circuit potential (OCP), electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization measurements. The results show that the corrosion behavior of both materials largely depends on patients. The obtained corrosion rates of both materials correspond well to the metal ion release rate detected in patients with joint implants revealing the adequateness of the electrochemical experimental protocol for quantifying in-vivo corrosion of biomedical implants. Based on the results, no significant risk of galvanic corrosion of Ti/CoCrMo coupling is anticipated. The rates of wear-accelerated corrosion (one of the main degradation mechanisms of metallic artificial hip joints) were theoretically extracted from the present electrochemical measurements using an established tribocorrosion model. Those material loss rates are patient-dependent and can be up to two orders of magnitude higher than the static corrosion rates, indicating that the nature of the patient can critically affect the degradation rate of the joint implant.

Influence of Al2O3 reinforcements and Ti-Al intermetallics on corrosion and tribocorrosion behavior of titanium

Ti-Al2O3 composites have demonstrated favorable characteristics for use in load-bearing biomedical implant applications; however, the influence of Al2O3 reinforcement particles and Ti-Al intermetallics on the electrochemical and tribo-electrochemical responses of Ti are not well-understood. This study explored the corrosion and tribocorrosion characteristics of powder metallurgy-manufactured Ti-Al2O3 composites in a simple physiological saline solution at body temperature. Electrochemical analysis was performed by electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization and tribo-electrochemical mechanisms were explored under open circuit potential (OCP) against a 10 mm diameter alumina ball in a ball-on-plate tribometer with reciprocating configuration. Results revealed that the corrosion behavior of Ti was adversely affected by the development of a heterogeneous oxide film on the Ti matrix and the Ti-Al intermetallic phases formed by the interaction of Ti and Al2O3 particles. However, there was a drastic improvement in tribocorrosion behavior, evidenced by decreased corrosion tendency under sliding and a marked reduction in wear volume, primarily as a result of the decreased wear damage resulting from the load-bearing reinforcements.

Effect of slight Sn modification on mechanical properties and corrosion behavior of Ti- (2–4 wt%) Mn alloys fabricated via powder metallurgy

The addition of Mn to Ti has been extensively investigated due to the remarkable biocompatibility and strength of Ti-Mn alloys, but their ductility was to prove insufficient, particularly for the powder metallurgy technology. In this study, Ti-2Mn, Ti-2Mn-2Sn, Ti-4Mn, and Ti-4Mn-2Sn alloys were manufactured by the powder metallurgy. The impact of slight Sn on the sintering densification, microstructure, mechanical properties, and electrochemical behavior of the Ti-(2–4 wt%) Mn alloys was researched. The findings indicate that a tiny amount of Sn effectively decreased the alloy's melting point, ideal sintering temperature, and sintering time. The addition of Sn didn't transform the lamellar structure of Ti-Mn alloy. In term of Ti-2Mn, Sn favoured the compressibility, played a beneficial effect in encouraging densification and refined the size of α and β phases. The ductility was significantly enhanced (15.9%), strength kept excellent (784 MPa) and corrosion resistance was improved, yielding in achieving a synergistic increase in strength, ductility and corrosion resistance. However, the addition of Sn in Ti-4Mn alloy hindered densification and promoted β phase coarsening, leading to little boost in ductility and deterioration of the corrosion resistance. Those findings could offer new insights to invent low-cost Ti alloys with wonderful performance.

Influence of Zirconium on the Corrosion Passivation of Titanium in Simulated Body Fluid

Pure Ti and 85%Ti-15%Zr alloy were sintered in a heat induction high frequency furnace. The corrosion behaviour of Ti and 85%Ti-15%Zr in simulated body fluid (SBF) was studied. The work was achieved using different techniques as the cyclic polarization (PCP), the impedance spectroscopy (EIS), and the change of the potentiostatic current with time (PCT) experiments. The morphology of the surfaces of Ti and Ti-Zr after being corroded in SBF for 72 were investigated by a scanning electron microscope (SEM) and the analysis for the layer formed on that surface was collected via energy dispersive X-ray (EDX). Results depicted that the 15% Zr present within Ti decreases the corrosion via increasing Ti corrosion resistance and minimizing its measured corrosion rate. PCP data proved that the addition of Zr reduced all anodic, cathodic and corrosion currents. EIS results confirmed that Zr has a positive impact on the reduction of corrosion resistance. PCT, SEM, and EDX examinations displayed that both Ti and Ti-Zr alloy don’t show pitting corrosion even after 72 h exposure to SBF.

Effect of Ni contents on mechanical properties and corrosion behavior of Ti(C,N)-WC-Mo2C-(Ni,Co) cermets

The mechanical properties and corrosion behavior of Ti(C,N)-WC-Mo2C-(Ni,Co) cermets with different Ni/Co ratios were investigated by mechanical property tests, scanning electron microscope, abrasion resistance test, electrochemical measurements, X-ray photoelectron spectroscopy. The results showed the increasing Ni content caused the improvement of fracture toughness and the reduction of hardness and abrasion resistance. Electrochemical tests indicated that the proper Ni addition in cermet may enhance the corrosion resistance with cermet in HCl and NaOH solution. The corrosion behavior of cermet was mainly determined by the selective dissolution of the binder phase and the formation of oxides on corroded surface. Moreover, the improving corrosion resistance of cermet in NaOH solution can be attribute to a dense passive film oxidized from binder phase. Hence, cermet with an appropriate ratio may be considered as promising structural material in complicated application with acid or alkali solution.

Studies on Ti, Zn and Ti + Zn Bilayer Coatings on Interstitial Free Steel for Enhancement of Wear and Corrosion Resistance

The present study concerns a detailed investigation of the microstructure, phase identity, composition, residual stress, wear and corrosion behavior of Ti, Zn and Zn + Ti coatings developed on IF steel by sputter deposition technique. A significant improvement in average microhardness (350-700 VHN) is noticed following sputter deposition compared to that of as-received IF steel (190 VHN). The highest microhardness recorded is 500 VHN for Ti, 350 VHN for Zn and 700 VHN for Ti + Zn bilayer, respectively. Improvement in surface hardness is accompanied by a marked improvement in wear resistance of the sputter-deposited surface against hardened steel ball. The corrosion rate of coated sample in 3.56 wt.% NaCl solution is marginally decreased (2.95 × 10−2 to 3.25 × 10−2 mm/year) as compared to that of as-received IF steel (3.55 × 10−2 mm/year). Ti-deposited IF steel registers the minimum corrosion rate (2.95 × 10−2 mm/year) among all the coated samples.

Studies on Corrosion of Titanium and Air-Oxidized Titanium in Fluorinated Nitric Acid

Titanium (Ti) is a lustrous transition metal which possesses excellent corrosion resistance in several aggressive environments but is attacked by acidic fluoride media. In this work, the addition of fluoride ion to nitric acid on the corrosion behavior of Ti and air-oxidized Ti was studied. Air oxidation of Ti at 800 °C for 5 h resulted in the formation of an intact rutile TiO2 layer with a thickness of about 35 μm. The corrosion resistance was investigated from the polarization resistance (R_{text{P}}) values which were obtained from linear polarization and electrochemical impedance spectroscopy (EIS) measurements. A decrease in the R_{text{P}} value of Ti with the addition of fluoride ion in nitric acid was observed, and this indicated the formation of an unstable layer, which resulted in accelerated dissolution. The several order increase in the R_{text{P}} value of air-oxidized Ti in nitric acid containing fluoride ions pointed the improved resistance to corrosion. The diffusivity of species through the air-oxidized TiO2 layer was estimated from the electrochemical equivalent circuit (EEC) analysis of EIS data. Even though the diffusivity increased by several orders with the addition of fluoride ions, air-oxidized Ti provided better protection against nitric acid containing fluoride ions than Ti. The corrosion rates of Ti and air-oxidized Ti in boiling nitric acid containing fluoride ions were also estimated from weight loss experiments. Even in boiling fluorinated nitric acid, air-oxidized Ti provided better corrosion protection, with corrosion rates of about 1000 times less than that of Ti.

Electrochemical corrosion behaviors of titanium covered by various TiO2 nanotube films in artificial saliva

TiO2 nanotube films obtained by anodization have shown great promise as biomaterials. In the present work, we report on the corrosion behaviors of titanium (Ti) with various TiO2 nanotubes prepared by using controlled anodization procedures. Special emphasis is put on the impact of film morphologies on the corrosion resistance of the Ti substrate. The corrosion behaviors of Ti with different nanotube films were studied in artificial saliva using open-circuit potential measurement, potentiodynamic polarization, and electrochemical impedance spectroscopy techniques. Ti covered by TiO2 nanotube films showed the markedly enhanced corrosion resistance properties compared to bare Ti. The existence of the compact oxide layer formed in a fluoride-free electrolyte was found to be beneficial for improving corrosion resistance properties. Besides, the TiO2 nanotube films obtained by two-step anodization had better corrosion resistance than those obtained by single-step anodization, though they used the identical anodization parameters.

Electrochemical Corrosion Behaviour of Ti–29Nb–13Ta–4.6Zr Alloy in Physiological Solution Containing Various Synovial Joint Lubricants

Ti alloys are well known for their biocompatibility and high specific strength. In the present work, the electrochemical behaviour of Ti–13Ta–29Nb–4.6Zr alloy having β structure in Hank’s solution containing various joint lubricants has been studied. The results show that Ti–13Ta–29Nb–4.6Zr alloy is a potential biomaterial for joint applications. The electrochemical behaviour of Ti–13Ta–29Nb–4.6Zr alloy is not influenced significantly by the nature of lubrication. The highest corrosion rate of investigated alloy is around 1.2 mm/year in Hyaluronic Acid containing Hank’s solution. The growth of passive layer is the slowest and the passive layer is the most porous in Hank’s solution containing hyaluronic acid.

Effect of Zr Addition on the Corrosion of Ti in Acidic and Reactive Oxygen Species (ROS)-Containing Environments.

The effect of systematic Zr additions on the corrosion behavior of Ti was studied in both acidic and reactive oxygen species (ROS) containing environments, including macrophage cell culture, simulating inflammation associated with metallic implants. Electrochemical measurements on commercially pure (CP) Ti, Zr, and TiZr alloys showed that increasing Zr additions progressively enhanced Ti passivity in both acidic (HCl) and oxidative (H2O2) environments. However, a Ti50Zr alloy was found with increased pitting susceptibility. Corrosion was also evaluated using mass-spectrometry to determine metal ion release following exposure of the alloys to THP-1 macrophage cell cultures, transformed into either their M1 (inflammatory states) or M2a (tissue repair states) phenotypes. The magnitude of ion release was reduced with increasing Zr contents, consistent with electrochemical observations. Nevertheless, optimized Zr content in Ti should balance both passivity and pitting resistance.

Hot Corrosion of Ti\u2013Re Alloys Fabricated by Selective Laser Melting

Selective laser melting (SLM) is an additive manufacturing process that enables novel alloy production by combining metals with significantly different physical properties. In this paper, the hot corrosion behavior of Ti–Re alloys fabricated by SLM was studied in a mixture of Na2SO4 and NaCl salts at 600 °C. The morphology and composition of the corrosion products were characterized by scanning electron microscopy with energy-dispersive X-ray spectroscopy and X-ray diffraction to understand the degradation mechanisms. It has been shown that the hot corrosion resistance of Ti–Re alloys was influenced by the chemical inhomogeneity of the oxide scale resulting from the presence of rhenium particles undissolved during the SLM process.

Corrosion Behavior of Ti and Zr in HF

Titanium and zirconium are used extensively in the industry due to their exceptional corrosion resistance in most of the harsh environments [1, 2]. Ti is used in aerospace industry, biomedical implantations, and in several chemical industries due to its low density, high mechanical strength and corrosion resistance [1]. Zr is mainly used as a fuel cladding material in nuclear industries and in chemical industries due to its high resistance to corrosion and H2embrittlement [2]. Although these materials exhibit high corrosion resistance in harsh acidic and alkaline environment, they readily dissolve in acidic fluoride media. The anodic polarization curves of Ti and Zr in HF [3,4] show that the active and passive regimes are clearly distinguishable . A comparison of these results also shows that Ti offers better passivation than Zr, in HF media. In this work, the effect of varying the concentration of HF on the corrosion rate was investigated using potentiodynamic polarization, linear polarization techniques and electrochemical impedance spectroscopy at open circuit potential (OCP). A rotating disk electrode of Ti/Zr was used in a three electrode cell with Ag/AgCl (in 3.5 M KCl) as reference and Pt wire as counter electrode. HF concentration was varied from 10 - 1000 mM for the corrosion rate estimation of Ti. Zr corrosion analysis was performed in 5 - 200 mM HF. In all the experiments, Na2SO4was used as the supporting electrolyte and the electrode was rotated at 900 rpm to suppress the mass transport limitations. Potentiodynamic polarization experiments were conducted at a scan rate of 2 mV/s, starting at 250 mV below open circuit potential (OCP) and ending at 250 mV above OCP. In case of Zr electrode dissolving in 100 and 200 mM HF, the scan rate was maintained at 20 mV/s, since a lower scan rate resulted in excessive corrosion of the material during the experiments. The potentiodynamic polarization curves of the Ti and Zr respectively are presented in Fig. 1A and Fig. 1B. The cathodic and anodic branches of potentiodynamic polarization were extrapolated to estimate the corrosion current using Tafel kinetics. HF is a weak acid and it forms multiple species in aqueous solutions. The concentration of these species was correlated and it is difficult to delineate the contribution of each species towards the corrosion current. Hence few experiments with addition of KF/H2SO4 were also carried out. The corresponding changes in the open circuit potential and corrosion current estimates were also analyzed. The concentration of various species, viz. remaining HF, H+, F-, HF2 - and H2F3 -, in the solution were calculated using the equilibrium constants [5]. The value of the polarization resistance (Rp) was calculated from the slope of linear polarization data. Electrical equivalent circuit fitting was used to calculate the polarization resistance from EIS spectra. The corrosion current was estimated using the values of Rp in all solutions. The values of the corrosion current estimated from the different techniques were compared. The correlation between the corrosion current and various solution species was also analyzed. The results indicate that the corrosion current is proportional to and where α and β are close to the exponents obtained from the mechanistic analysis of the polarization curves [3, 4]. The morphology of the electrodes after the passivation was studied using atomic force microscopy (AFM) and it shows less roughness compared to the active region of dissolution. The AFM images showed lesser passivation for Zr metal compared to Ti. These observations provide insight to the difference in the corrosion prevention of the two metals regardless of the same group in the periodic table.

Electrochemical study on the corrosion behavior of Ti3SiC2 in 3.5% NaCl solution

The differences between the Ti–C and Ti–Si chemical bonds limit the passivation ability, resulting in a decreased passivation ability.

Acid corrosion behaviour of Ti–48Al–6Nb porous alloys with different phase skeletons

Ti–48Al–6Nb porous alloys with different phase skeletons were synthesised by powder metallurgy at different temperatures. TiAl3 skeletons achieved at 700°C were covered by corrosion products and skeletons fractures led to pores collapse. TiAl skeletons were synthesised at 900°C with obvious corrosion pits and pore diameter increasing. And Ti3Al/TiAl skeletons achieved at 1350°C exhibit the best acid corrosion resistance with the least mass loss of 1.853 mg m–2. Skeletons and pore diameters remained stable just with fully lamellar structures emerged. In addition, Nb2Al phases presented better resistance than NbAl3 in the skeletons contributing to acid corrosion resistance of the porous alloys.

Corrosion behaviour of Ti–10Mo–4Zr AND Ti–6Al–4V alloysin the hank's soluton: influence of pH and alloying elements

Corrosion behaviour of Ti–10Mo–4Zr AND Ti–6Al–4V alloysin the hank's soluton: influence of pH and alloying elements

Corrosion Behavior of Ti and Ti Based Alloys Used as Implants-Supported Mandibular Overdentures

In the present study, four different types of the commercial dental implants used as support for total/partial dental prosthesis have been investigated. Pure Ti and Ti6Al4V alloy, provided by four different manufactures, were chosen because these were the most used in dentistry market. The corrosion resistance was evaluated by using linear polarization technique, after recording the open circuit curves in Fusayama Meyer artificial saliva for 240 minutes. The corrosion tests in artificial saliva with pH 5.2 have shown that pure Ti exhibited a better behavior than the Ti alloy. This result can be explained by a higher stability of the passive thin layer of titanium oxide than the complex oxide layer formed on the Ti alloy surface.

Corrosion behavior of Ti(C,N)-Ni/Cr cermets in H2SO4 solution

The effects of partial substitution of Ni with Cr on the microstructure and corrosion resistance of Ti(C,N)-based cermets in H2SO4 solution were investigated in this paper. The results showed that partial substitution of Ni with Cr had a minor effect on the microstructure, whereas the hardness of the Ti(C,N)-based cermets could be improved for dissolution of Cr in Ni binder. The corrosion behavior of Ti(C,N)-based cermets with different Cr content in 0.2mol/L H2SO4 solution was also studied via potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and corrosion test. The tested Ti(C,N)-Ni/Cr cermets had three typical passive regions. The current of the first passive region was reduced and the passive range was enlarged with the increase of Cr content in binder attributed to the synergistic effect of Ti-based and Cr-based passive layers. But the remaining passive regions were pseudopassive regions. The EIS results also demonstrated that the impendence of the reaction rose with the increase of Cr content in binder. Moreover, the corrosion resistance of cermets in H2SO4 solution was improved remarkably by Cr dissolving in the binder, which gave rise to the enhanced passivation ability.