Effect of Heat Treatment and Boron Addition on Corrosion Behavior of Ti-35Nb-7.2Zr-5.7Ta (wt%) β-Titanium Alloy in Simulated Body Fluid

CORROSION ◽  
2011 ◽  
Vol 67 (8) ◽  
pp. 085001-1-085001-9 ◽  
Author(s):  
P. Majumdar ◽  
S.B. Singh ◽  
U.K. Chatterjee ◽  
M. Chakraborty
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Corrosion Behavior ◽  
Current Density ◽  
Titanium Boride ◽  
Corrosion Current ◽  
Treatment Conditions ◽  
Heat Treated ◽  
Passive Current ◽  
Hank’S Solution

Abstract The corrosion behavior of Ti-35Nb-7.2Zr-5.7Ta (TNZT) and Ti-35Nb-7.2Zr-5.7Ta-0.5B (TNZTB) alloys subjected to different heat treatment conditions was investigated in Hank's solution. Depending on the heat treatment conditions, the microstructure of the water-quenched, single-stage aged or duplex aged samples consists of very small amounts of ω or α precipitates in equiaxed β grains. Addition of boron to the TNZT alloy results in the formation of dispersed precipitates of titanium boride (TiB) in the β matrix. The other features present in the TNZTB alloy are similar to those in the TNZT alloy. Compared with single aging, duplex aging decreases the corrosion potential (Ecorr) and substantially decreases corrosion current density (icorr) and passive current density (ipass) values. Addition of boron to the TNZT alloy shifts the Ecorr value toward a more active direction and increases the icorr as well as ipass values significantly, and therefore deteriorates the corrosion resistance of the titanium alloys. In general, duplex aged TNZT samples show better corrosion resistance than other heat-treated TNZT or TNZTB samples.

Surface Treatments of Stainless Steel by Electroless Silver Coatings as a Bipolar Plate for Proton Exchange Membrane Fuel Cells

2015 ◽  
Vol 12 (6) ◽  
Author(s):  
Ing-Bang Huang ◽  
Ching Chiang Hwang
Keyword(s):  
Corrosion Resistance ◽  
Fuel Cell ◽  
Current Density ◽  
Corrosion Current Density ◽  
Proton Exchange Membrane ◽  
Corrosion Current ◽  
Proton Exchange ◽  
Heat Treated Sample ◽  
Heat Treated ◽  
Exchange Membrane

The objective of this study is to examine the effect of heat treatment at various temperatures on the corrosion behavior of electroless silver-coated SS 304 in a simulated proton exchange membrane (PEM) fuel cell environment. The corrosion properties of this material were studied using a potentiodynamic polarization technique. X-ray diffraction (XRD) patterns, polarization curves, and scanning electron microscopy (SEM) of coated and heat-treated specimens obtained in various heating temperatures were also utilized. It was found that the corrosion potential of the coated and heat-treated specimens shift toward a noble potential, and a significant decrease in corrosion current density was also observed. The corrosion current density decreased by a factor of about 1/500 for the heat-treated sample of 600 °C compared to the substrate. The heat-treated specimens displayed greater corrosion resistance than unheated and bare ones. According to the polarization studies and SEM images, the heat-treated specimen at 600 °C shows excellent corrosion resistance with a homogeneous dense surface morphology. These results demonstrated the coatings were suited for fuel cell applications in the proton exchange membrane fuel cell (PEMFC) environment.

Effects of Heat Treatment and Alloying of Spheroidal Graphite Cast Iron on Corrosion Resistance in Aqueous Environment

2004 ◽  
Vol 449-452 ◽  
pp. 533-536
Author(s):  
M. Aoyama ◽  
K. Tahashi ◽  
K. Matsuno
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Cast Iron ◽  
Current Density ◽  
Electrode Potential ◽  
Corrosion Current ◽  
Spheroidal Graphite ◽  
Spheroidal Graphite Cast Iron ◽  
Graphite Cast Iron ◽  
The Matrix

The present study examined the effects of heat treatment and the addition of Cu-Ni alloy on the corrosion resistance of the matrix of spheroidal graphite cast iron in aqueous environments. Test materials of white cast iron and carbon steel were used for comparison with spheroidal graphite cast iron. The alloy spheroidal graphite cast iron that added Cu and Ni was prepared. The spheroidal graphite cast iron was subjected to three kinds of heat treatment to adjust the matrix: annealing, oil quenching, and austemper heat treatment. In electrochemical tests, measurements of corrosion electrode potential and cathode and anode polarization were used. The following was clarified from the relationship between the electrode potential and current density of each of the materials in each of the solution. The alloy spheroidal graphite cast iron had a high corrosion electrode potential owing to the addition of Cu-Ni, and tended to have a low corrosion current density. This demonstrates that in any of the materials having a matrix adjusted by heat treatment, the addition of Cu-Ni increased the corrosion resistance. The corrosion current density was highest in a sulfuric acid environment.

Effect of High-Intensity Pulsed Ion Beam Irradiation on the Electrochemical Corrosion Behavior of AZ31 Magnesium Alloy

2011 ◽  
Vol 189-193 ◽  
pp. 571-574
Author(s):  
Peng Li
Keyword(s):  
Corrosion Resistance ◽  
Magnesium Alloy ◽  
Corrosion Behavior ◽  
Current Density ◽  
Ion Beam ◽  
Electrochemical Corrosion ◽  
Corrosion Current ◽  
Open Circuit ◽  
Electrochemical Corrosion Behavior ◽  
Shot Number

HIPIB irradiation experiment is carried out at a specific ion current density of 1.1 J/cm2 with shot number from one to ten in order to explore the effect of shot number on electrochemical corrosion behavior of magnesium alloy. Surface morphologies, microstructure and corrosion resistance of the irradiated samples are examined by scanning electron microscopy (SEM), transmission electron microscope (TEM) and potentiodynamic polarization technique, respectively. It is found that HIPIB irradiation leads to the increase in open circuit potential, corrosion potential and breakdown potential, and the decrease in the corrosion current density and the corrosion rate as compared to the original sample. The improved corrosion resistance is mainly attributed to the grain refinement and surface purification induced by HIPIB irradiation.

Structure and corrosion behavior of Al-Co-Ti alloy system

2017 ◽  
Vol 64 (4) ◽  
pp. 443-451 ◽  
Author(s):  
Mohamed Yacine Debili ◽  
Nacira Sassane ◽  
Noureddine Boukhris
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Corrosion Behavior ◽  
Alloy System ◽  
Ambient Air ◽  
Corrosion Current ◽  
Electrochemical Characteristics ◽  
Ti Alloy ◽  
Mixed Powder ◽  
Content Type

Purpose This paper aims to investigate ternary Al-Co-Ti alloy system with various Co compositions. Structural characterization of AlxCoy-2Ti2 alloys were performed by means of light microscopy, scanning electron microscopy, X-ray diffraction and electrochemical test. The effect of the addition of 5, 10, 15, 20, 25, 30 per cent Co and 2 per cent Ti on the structural evolution shows that both intermetallic compounds formation and structure morphology are related to corrosion resistance at the as-elaborated state as after subsequent heat treatment at 500°C during short time. According to the microstructural characterizations, the authors can notice that the substitution of Co has an important effect on the corrosion resistance and plays a role for the formation of the passive film. Design/methodology/approach The alloys in this study were obtained by a high-frequency induction fusion. Powders from Al, Co and Ti (99.999 per cent) in proportions defined according to the composition aimed of alloy have been used. The total mass of the sample to be elaborated lies between 8 and 10 g. Cold compaction was achieved for mixed powder intended for high fusion frequency (HF). For electrochemical tests, the sample was cut by a diamond wheel to obtain a square section of dimensions 1 cm2. Afterward, this sample was connected with a Cu electrical wire. The last stage is the envelope in an acrylic resin realized in a plastic mold. The used electrolyte is a salt environment of 3.5 per cent NaCl (35 g of NaCl by liter of distilled water at room temperature [25 ± 1°C], aerated and with moderated agitation V = 250 r.min−1). This mold is kept in ambient air for 10 min to allow the resin to solidify. Findings The aim of this work is to establish the influence of the addition of Co and Ti on structural change and related corrosion behavior improvement in Al. Particular attention is accorded to Al-15 per cent Co-2 per cent Ti alloy. Originality/value Among the studied alloys with different Co contents, a precise composition of 15 per cent Co and 2 per cent Ti appears to have interesting electrochemical characteristics regarding the corrosion potential, the corrosion current and particularly the corrosion rate, which is very small when compared to that of other alloys, as well in the as-solidified state than after heat treatment. This composition is located halfway between the stainless steel 304 and the Al-Fe and Al-Co-Ce alloys.

scholarly journals Corrosion Behavior of As-Cast Ti–10Mo–6Zr–4Sn–3Nb and Ti–6Al–4V in Hank’s Solution: A Comparison Investigation

Metals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 11
Author(s):  
Jun Cheng ◽  
Jinshan Li ◽  
Sen Yu ◽  
Zhaoxin Du ◽  
Fuyu Dong ◽  
...  
Keyword(s):  
Corrosion Behavior ◽  
Current Density ◽  
Oxygen Vacancies ◽  
Corrosion Potential ◽  
Corrosion Current ◽  
X Ray Diffraction ◽  
X Ray ◽  
Biomedical Material ◽  
Passivation Current Density ◽  
Hank’S Solution

Newly developed Ti–10Mo–6Zr–4Sn–3Nb has fascinating mechanical properties to be used as a biomedical material. However, there is still a lack of investigation focusing on the corrosion behavior of Ti–10Mo–6Zr–4Sn–3Nb. In this work, the microstructure and corrosion behavior of as-cast Ti–10Mo–6Zr–4Sn–3Nb was investigated by optical microscopy, X-ray diffraction, and electrochemical measurements. Hank’s solution was used as the electrolyte. A classical as-cast Ti–6Al–4V was used as reference. The results showed that Ti–10Mo–6Zr–4Sn–3Nb has a higher corrosion potential and a lower corrosion current density compared with Ti–6Al–4V, indicating better corrosion resistance. However, after applying anodic potentials, Ti–10Mo–6Zr–4Sn–3Nb shows larger passivation current density in both potentiodynamic polarization and potentiostatic polarization tests. This is because more alloying elements contained in Ti–10Mo–6Zr–4Sn–3Nb trigger the production of a larger number of oxygen vacancies, resulting in a higher flux of oxygen vacancy. This finding illustrates that the passive film on Ti–10Mo–6Zr–4Sn–3Nb is less protective compared with that on Ti–6Al–4V when applying an anodic potential in their passivation range.

scholarly journals Corrosion Behavior of Diffusion Bonding Joints of (OFHC) Copper with Stainless Steel 304L in 3.5% NaCl

2018 ◽  
Vol 21 (1) ◽  
pp. 74
Author(s):  
Sami Abualnoun Ajeel ◽  
Ahmed Ali Akbar Akbar ◽  
Safaa Mohammed Hassoni
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
Corrosion Behavior ◽  
Current Density ◽  
Diffusion Bonding ◽  
Corrosion Current Density ◽  
Pure Copper ◽  
Corrosion Current ◽  
Stainless Steel 304L ◽  
Materials Used

The present work deals with direct diffusion bonding welding without interlayer of austenitic stainless steel type AISI 304L with Oxygen Free High Conductivity pure copper (OFHC) in vacuum atmosphere (1.5 *10-5 mbr.). The optimum bonding conditions are temperature of 650 ◦C, duration time of 45 min. and the applied stress of 30 MPa, in order to secure a tight contact between the mating surfaces. The corrosion behavior of diffusion bonding joints in 3.5% Nacl is studied to evaluate the corrosion resistance of welding joints by using Potentiodynamic method. The observed microstructure of corroded specimen of optimum diffusion bonding joint shows that the corrosion current density has low value as compared with base materials used. During polarization, galvanic coupling is observed between two materials used. At passivity region, inverse polarity is occurred at 450mV. Therefore, passive stainless steel 304 L behaves as cathode respective to pure copper, the corrosion behavior of the diffusion bonding joint was mostly by copper side. The corrosion results indicate the presence of galvanic effect. The corrosion current density of copper, stainless steel 304L and bond joints condition were (3.66 µA/cm2, 1.62 µA/cm2 and 1.85µA/cm2) respectively. A SEM examination of corroded diffusion bonding joint indicates that the galvanic corrosion happened on copper side. The corrosion rate of bonding joint conditions was 0.85 mpy, which is less than 1%. This means that corrosion resistance of bond joint is more than excellent.

scholarly journals Influence of Boron Addition on the Microstructure and the Corrosion Resistance of CoCrMo Alloy

Metals ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 307 ◽  
Author(s):  
Marco Hernandez-Rodriguez ◽  
Dionisio Laverde-Cataño ◽  
Diego Lozano ◽  
Gabriela Martinez-Cazares ◽  
Yaneth Bedolla-Gil
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Electrochemical Impedance ◽  
Passive Layer ◽  
Boron Addition ◽  
Joint Replacements ◽  
Treatment Conditions ◽  
Wear And Corrosion ◽  
Heat Treated ◽  
Wear And Corrosion Resistance

Cobalt-based alloys are extensively used in orthopedic applications for joint replacements due to their wear and corrosion resistance. Corrosion, however, is often associated with fatigue failure in these orthopedic devices. In this study, the effect of boron addition on the corrosion behavior of CoCrMo alloys was studied using linear polarization resistance, potentiodynamic polarization curves, electrochemical impedance spectroscopy, and cyclic voltammetry. The samples were analyzed under as-cast and heat treatment conditions after 21 days of immersion in phosphate-buffered saline (PBS) solution at 37 °C. The boron addition increased the particle content, while the heat treatment promoted enlargement and even distribution of the precipitates throughout the structure. The corrosion resistance was improved by both boron and heat treatments. The best performance was observed for a heat-treated alloy having a very small amount of boron, which had an increased resistance to corrosive attack. Such behavior was attributed to the homogenized microstructure achieved by boron and heat treatment that helped to form a stable passive layer of chromium oxide which endured the 21 days of immersion.

Influence of Cr and Mn Addition and Heat Treatment on the Corrosion Behaviour of an AlSi3Mg Alloy

2017 ◽  
Vol 754 ◽  
pp. 11-14 ◽  
Author(s):  
Marialaura Tocci ◽  
Lorenzo Montesano ◽  
Annalisa Pola ◽  
Marcello Gelfi ◽  
Marina La Vecchia
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Corrosion Resistance ◽  
Corrosion Current Density ◽  
Corrosion Behaviour ◽  
Base Alloy ◽  
Corrosion Current ◽  
Nacl Solution ◽  
Heat Treated ◽  
Mechanical Properties And Corrosion

In the present work, the effect of Cr and Mn addition on corrosion resistance was investigated on AlSi3Mg alloy. Potentiondynamic corrosion tests in a 3.5 wt. % NaCl solution were performed on samples in different heat-treated conditions, and corrosion current density and potential were determined by Tafel method. Brinnel hardness measurements were also carried out in order to couple corrosion resistance with mechanical properties. It was interestingly found that Cr presence enhanced mechanical properties and corrosion resistance in comparison with the base alloy.

scholarly journals Effect of Recrystallization Annealing on Corrosion Behavior of Ta-4%W Alloy

Materials ◽  
2018 ◽  
Vol 12 (1) ◽  
pp. 117 ◽  
Author(s):  
Guoqiang Ma ◽  
Qiongyao He ◽  
Xuan Luo ◽  
Guilin Wu ◽  
Qiang Chen
Keyword(s):  
Corrosion Resistance ◽  
Anodic Dissolution ◽  
Corrosion Behavior ◽  
Current Density ◽  
Polarization Resistance ◽  
Corrosion Current Density ◽  
Corrosion Potential ◽  
Corrosion Current ◽  
Recrystallization Annealing ◽  
Site Lattice

The effect of recrystallization annealing on corrosion behavior of Ta-4%W alloy was studied. It is found that the deformed sample contains high dense dislocations and dislocation boundaries. During annealing, these dislocations and dislocation boundaries are replaced by recrystallizing grains until the alloy is fully recrystallized. Both the anodic dissolution and the cathodic activity is much more blocked. The corrosion potential gradual shift towards negative values and corrosion current density decrease, while polarization resistance increases after annealing, indicating enhanced corrosion resistance of the alloy. Such an enhancement is caused by the increase of low-Σ coincide site lattice boundaries and decrease of dislocations and dislocation boundaries.

Effect of Destabilisation and Tempering Heat Treatments on Hardness and Corrosion Behavior of 28 wt.%Cr Cast Irons with Mo Addition

2018 ◽  
Vol 283 ◽  
pp. 95-100
Author(s):  
Amporn Wiengmoon ◽  
Napachat Tareelap ◽  
Suttawan Imurai ◽  
Torranin Chairuangsri ◽  
John T.H. Pearce
Keyword(s):  
Corrosion Resistance ◽  
Corrosion Behavior ◽  
Current Density ◽  
Heat Treatments ◽  
Phase Identification ◽  
Cast Irons ◽  
Aqueous Corrosion ◽  
Eutectic Carbides ◽  
Aqueous Corrosion Resistance ◽  
Passive Current

The effects of destabilisation and tempering heat treatments on hardness and corrosion behavior in 28 wt.%Cr-2.6 wt.%C cast irons with up to 6 wt.%Mo addition were studied. The irons were destabilised at 1025 °C for 4 h and air cooled. Tempering was carried out at 450 °C for 4 h. Phase identification and microstructure were investigated by X-ray diffraction (XRD), light microscope (LM), scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). Vickers macro-hardness was measured. A potentiodynamic technique was used to indicate aqueous corrosion resistance. The results revealed that the as-cast microstructure of 28 wt.%Cr iron consisted of primary austenite dendrites with eutectic M7C3 carbides. In the irons with 6 wt.%Mo addition, eutectic carbides including M7C3, M23C6 and M6C were found. After destabilisation, the microstructure contained secondary carbide precipitates within an essentially martensitic matrix. Vickers macro-hardness of the as-cast and destabilised irons increased from 500 HV30 and 736 HV30 in the 28 wt.%Cr iron up to 570 HV30 and 870 HV30 in the iron with 6 wt.%Mo addition. Tempering slightly increased the macro-hardness. The as-cast 28 wt.%Cr iron had the lowest values for critical current density and passive current density. The destabilised + tempered treatment gave the lowest corrosion resistance.

Sign in / Sign up

Export Citation Format

Share Document