scholarly journals Long Term Corrosion Experiment of Steel Rebar in Fly Ash-Based Geopolymer Concrete in NaCl Solution

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
Y. P. Asmara ◽  
J. P. Siregar ◽  
C. Tezara ◽  
Wan Nurlisa ◽  
J. Jamiluddin
Keyword(s):  
Fly Ash ◽  
Corrosion Rate ◽  
Corrosion Behaviour ◽  
Electrochemical Measurement ◽  
Corrosion Current ◽  
Electrochemical Process ◽  
Concrete Mixture ◽  
Nacl Solution ◽  
Polarization Diagram ◽  
Cell Potential

This research focuses on an experimental investigation to identify the effects of fly ash on the electrochemical process of concrete during the curing time. A rebar was analysed using potentiostat to measure the rest potential, polarization diagram, and corrosion rate. Water-to-cement ratio and amount of fly ash were varied. After being cured for 24 hours at a temperature of 65°C, the samples were immersed in 3.5% of NaCl solution for 365 days for electrochemical measurement. Measurements of the half-cell potential and corrosion current density indicated that the fly ash has significant effects on corrosion behaviour of concrete. Although fly ash tends to create passivity on anodic current, it increases corrosion rate. The corrosion potential of this concrete mixture decreases compared to concrete without fly ash. From the result, it can be summarized that concrete mixture with 70% of OPC (Ordinary Portland Cement) and 30% fly ash has shown the best corrosion resistance.

scholarly journals Corrosion behaviour of an AlZnSnSrGa alloy in aqueous solutions of NaCl and Na2So4

2000 ◽  
Vol 65 (1) ◽  
pp. 73-81
Author(s):  
P. Zivkovic ◽  
J. Pjescic ◽  
S. Mentus
Keyword(s):  
Corrosion Rate ◽  
Aqueous Solutions ◽  
Polarization Resistance ◽  
Corrosion Current Density ◽  
Corrosion Behaviour ◽  
Base Material ◽  
Corrosion Current ◽  
Open Circuit ◽  
Base Metals ◽  
Aluminium Plant

The alloy composed of Al(95.53%), Zn(2.85%), Sn(0.515%), Ga(0.1%) and Sr(0.009%), with the weight percents in the parentheses, was prepared by melting, using Al(99.84%), a product of the Aluminium Plant-Podgorica, as the base material. The corrosion behaviour of this alloy was tested in relation to the behaviour of the base metals, by both open curcuit potential and polarization resistance methods, in aqueous solutions of both NaCl and Na2SO4, the concentration of which varied within the range 0.00051 - 0.51 mol dm -3. Over the whole salt concentration ranges, the corrosion parameters indicate that the corrosion rate of the alloy is significantly higher than the rate of the base material. For instance, for the concentration range 0.00051 - 0.51 mol dm -3 , the stationary open circuit potentials, related to SCE, in NaCl solutions were - 1.200 to - 1.460 V for the alloy and - 0.693 to - 0.920 V for Al, while in Na2SO4 solutions, the stationary open circuit potentials were - 1.190 to - 1.465V for the alloy and - 0.780 to - 0.860V for Al. At the same time, the corrosion current density in NaCl solutions varied within 11-89 mA cm -2 for the alloy and 0.35 - 0.80 for Al, while in Na2SO4 solutions it amounted to 5.7.52 mA cm -2 for the alloy and 0.28 - 0.88 mA cm -2 for Al.

Corrosion Behaviour of Aluminium Alloy in Palm Oil Methyl Ester (B100)

2012 ◽  
Vol 58 (2) ◽  
Author(s):  
W. B. Wan Nik ◽  
S. Syahrullail ◽  
R. Rosliza ◽  
M. M. Rahman ◽  
M. F. R. Zulkifli
Keyword(s):  
Weight Loss ◽  
Methyl Ester ◽  
Corrosion Rate ◽  
Aluminium Alloy ◽  
Palm Oil ◽  
Corrosion Behaviour ◽  
Corrosion Current ◽  
Electrochemical Test ◽  
Weight Loss Method ◽  
Loss Method

The aim of this study is to determine the corrosion effect of palm oil methyl ester (POME) on aluminium alloy 5083 (AA5083). The static immersion test was carried out at 60°C for 68 days according to ASTM G–31–72. The corrosion analysis was done by using weight loss method and electrochemical test. The result from weight loss method shows the decreasing in weight loss of AA5083 which signifies the ability of POME to reduce corrosion rate. The electrochemical test shows the decreasing in polarization resistance,Rp, while the corrosion current densities, Icorr, increase. The corrosion rate reduces from 2.250mpy to 0.1946mpy. The low concentration of fatty acid C18:2 and high anti oxidant element contributes to the reduction of corrosion rate of AA5083 in POME.

scholarly journals Evaluation of Corrosion Resistance in 3.5% NaCl Solution of Hybrid Coatings Obtained from Plastics Materials

2021 ◽  
Vol 58 (1) ◽  
pp. 201-209
Author(s):  
Alina Crina Muresan ◽  
Daniela Laura Buruiana ◽  
Gabriel Bogdan Carp ◽  
Sorin Berbece ◽  
Constantin Trus
Keyword(s):  
Corrosion Resistance ◽  
Corrosion Rate ◽  
Disperse Phase ◽  
Phenol Formaldehyde ◽  
Corrosion Current ◽  
Phenol Formaldehyde Resin ◽  
Hybrid Coatings ◽  
Formaldehyde Resin ◽  
Nacl Solution ◽  
Plastic Materials

In this work, the corrosion resistance of hybrid coatings obtained from plastic materials was evaluated and compared with the corrosion resistance of Zn coatings. Zinc and hybrid coatings were obtained by electrodeposition from zinc sulphate electrolyte. For obtained hybrid coatings it was used as disperse phase two type of plastic materials: phenol-formaldehyde resin and epoxy resin. Polarization was used to measure the corrosion rate and behaviour of zinc and hybrid coatings in 3.5% NaCl solution. Tafel curves show that the including particles of plastic materials in zinc matrix disturbs the cathodic reactions and reduces anodic reaction leading to decrease of corrosion current and increase the corrosion resistance of hybrid coatings obtained at the same electrodeposition parameters as zinc coatings. Smallest values of corrosion rate were evaluated for hybrid coatings obtained with phenol-formaldehyde resin as disperse phase that indicates a good corrosion resistance in 3.5% NaCl solution.

scholarly journals Effect of Sr and Ti Addition on the Corrosion Behaviour of Al-7Si-0.3Mg Alloy

2017 ◽  
Vol 17 (2) ◽  
pp. 125-130 ◽  
Author(s):  
M. Uludağ ◽  
M. Kocabaş ◽  
D. Dışpınar ◽  
R. Çetin ◽  
N. Cansever
Keyword(s):  
Mechanical Properties ◽  
Corrosion Resistance ◽  
Corrosion Rate ◽  
Potentiodynamic Polarization ◽  
Corrosion Test ◽  
Corrosion Behaviour ◽  
Tensile Tests ◽  
Nacl Solution ◽  
Cyclic Potentiodynamic Polarization ◽  
Ti Addition

AbstractIn the present study, the corrosion behaviour of A356 (Al-7Si-0.3Mg) alloy in 3.5% NaCl solution has been evaluated using cyclic/potentiodynamic polarization tests. The alloy was provided in the unmodified form and it was then modified with AlTi5B1 for grain refinement and with AlSr15 for Si modifications. These modifications yield to better mechanical properties. Tensile tests were performed. In addition, bifilm index and SDAS values were calculated and microstructure of the samples was investigated. As a result of the corrosion test, the Ecorr values for all conditions were determined approximately equal, and the samples were pitted rapidly. The degassing of the melt decreased the bifilm index (i.e. higher melt quality) and thereby the corrosion resistance was increased. The lowest corrosion rate was founded at degassing and as-received condition (3.9x10-3mm/year). However, additive elements do not show the effect which degassing process shows.

ZnO Nanoparticles for Anti-Corrosion Nanocoating of Carbon Steel

2017 ◽  
Vol 894 ◽  
pp. 76-80 ◽  
Author(s):  
J.N. Hasnidawani ◽  
Noor Azlina Hassan ◽  
Hassan Norita ◽  
Noorasikin Samat ◽  
Noor Najmi Bonnia ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Carbon Steel ◽  
Corrosion Rate ◽  
Mild Steel ◽  
Corrosion Behaviour ◽  
Oxide Coating ◽  
Immersion Test ◽  
Nacl Solution ◽  
Corrosion Resistant ◽  
Naoh Solution

Nanostructured coatings offer great potential for various applications due to their superior characteristics that are not typically found in conventional coatings. This research aimed at developing a new and improved coating that employs zinc oxide nanopowder as the agent to achieve corrosion resistant properties for a coating. The research project discusses on its corrosion behaviour of epoxy-zinc oxide in different media by measuring its corrosion rate. Mild carbon steel was used as the substrate for the epoxy-zinc oxide coating. The corrosion behavior mechanism of mild steel was investigated in different media, namely fresh water, NaCl solution, HCl solution and NaOH solution. Immersion test was conducted and studied for a period of 60 days, with daily and weekly weighing and immersing. The corrosion rate was calculated and mild steel corrodes in the different environment and degrades in the following trend; HCl → NaCl → NaOH → H2O.

scholarly journals Effect of Fe, Ni and Cr on the corrosion behaviour of hypereutectic Al-Si automotive alloy in 3.5% NaCl solution at different temperature and velocity

2019 ◽  
Vol 48 (1) ◽  
pp. 11-17
Author(s):  
M. S. Kaiser ◽  
S. H. Sabbir ◽  
M. Rahman ◽  
M. S. Kabir ◽  
M. Al Nur
Keyword(s):  
Corrosion Rate ◽  
Aluminum Oxide ◽  
Corrosion Behaviour ◽  
Experimental Information ◽  
Solution Temperature ◽  
Nacl Solution ◽  
Velocity Increase ◽  
X Ray ◽  
Optical Micrograph ◽  
Intermetallic Particles

The main focus of this study is to examine and evaluate the effect of Fe, Ni and Cr on the corrosion behaviour of hypereutectic Al-Si automotive alloy in 3.5% NaCl solution. Experimental information are attained using conventional gravimetric measurements under different solution temperature and velocity and complemented by resistivity, optical micrograph, scanning electron microscopy (SEM) and X-ray analyzer (EDX) investigations. All the alloys show the negative corrosion rate due to formation of a very thin film of aluminum oxide and hydroxid on the surface. Intermetallic particles in the alloys play a major role in passivity. Temperature accelerates the corrosion and the higher velocity breakdown of the passive film. It also affects the resistivity of the alloys. The results from this study also indicate that the temperature and velocity increase the negative corrosion rate of the alloys due to higher rate of chemical reactions. SEM and EDX analysis indicate that the surfaces compose with a thin layer of aluminum oxide and hydroxide corrosion products.

Corrosion Behaviour of Duplex Treated EN 42CrMo4 Steel by Gas Nitriding and TiAlN PAPVD Deposition

2016 ◽  
Vol 1138 ◽  
pp. 159-164
Author(s):  
Ramona Monica Buzdugan ◽  
Mircea Dan ◽  
Iosif Hulka ◽  
Monica Dome ◽  
Anamaria Feier ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Corrosion Rate ◽  
Linear Polarization ◽  
Corrosion Behaviour ◽  
Nacl Solution ◽  
Gas Nitriding ◽  
Duplex Treatment ◽  
42Crmo4 Steel

A Duplex treatment consisting in gas nitriding followed by PAPAVD deposition of TiAlN has been proposed as a solution for improving the corrosion behaviour of EN 42CrMo4 steel. The corrosion resistance in 3.5% NaCl solution was evaluated by linear polarization. It was found that the Duplex treated samples exhibited better corrosion resistance and that the corrosion rate decreased significantly from 0.069 mm an-1 (untreated samples) to 0.008 mm an -1 (Duplex treated).

scholarly journals Corrosion Evaluation of Geopolymer Concrete Made with Fly Ash and Bottom Ash

2021 ◽  
Vol 13 (1) ◽  
pp. 398
Author(s):  
Priyanka Morla ◽  
Rishi Gupta ◽  
Peiman Azarsa ◽  
Ashutosh Sharma
Keyword(s):  
Fly Ash ◽  
Corrosion Rate ◽  
Corrosion Behavior ◽  
Bottom Ash ◽  
High Rate ◽  
Geopolymer Concrete ◽  
Cell Potential ◽  
Accelerated Corrosion ◽  
Corrosion Evaluation ◽  
Alumino Silicate

Environmental pollution caused by CO2 releasing from the production of cement is a great challenge for the construction industry and has triggered exploration into more sustainable alternatives. Geopolymer Concrete (GPC) is a potential sustainable solution that does not involve the use of cement as a binder. GPC is produced by mixing the alumino-silicate source materials such as fly-ash with alkali activators such as potassium hydroxide (KOH) and potassium silicate (K2SiO3). Unlike Ordinary Portland Concrete (OPC), the characteristics of GPC depend on the precursor materials and therefore vary for different mixes. Consequently, corrosion behavior needs to be evaluated separately for individual mixes. This has narrowed the scope of existing published work on corrosion behavior of GPC. In this study, GPC and OPC specimens were prepared and exposed to accelerated corrosion exposure. Half-cell potential and linear polarization resistance were used to evaluate the corrosion rate in GPC and OPC. Under accelerated conditions, the corrosion rate of the GPC specimens was between 10 µm/year and 20 µm/year exhibiting a moderate to high rate of corrosion. Meanwhile, the corrosion rate of the OPC specimens was between 40 µm/year and 60 µm/year indicating a very high corrosion activity. It can be concluded that GPC has a higher resistance to chloride-induced corrosion; with a low corrosion rate and lower mass loss percentage, compared to OPC.

Effectiveness of an Inorganic Corrosion Inhibitor in Pore Solution Containing Sodium Chloride

2014 ◽  
Vol 556-562 ◽  
pp. 158-161 ◽  
Author(s):  
Xing Guo Feng ◽  
Guang Hui Dong ◽  
Jun Yan Fan
Keyword(s):  
Weight Loss ◽  
Sodium Chloride ◽  
Corrosion Rate ◽  
Corrosion Current Density ◽  
Inhibition Efficiency ◽  
Corrosion Potential ◽  
Pore Solution ◽  
Electrochemical Measurement ◽  
Corrosion Current ◽  
Organic Inhibitor

Combining use electrochemical measurement and weight loss testing, the inhibition efficiency of an organic inhibitor was studied in a chloride contaminated solution. The results showed that the added inhibitor can enhance the corrosion potential and decreased the corrosion current density of rebar. The weight loss testing confirmed that the inhibitor reduced the corrosion rate of rebar by 80% in the chloride containing solution. Moreover, the linear polarization results are consistent with the weight loss testing, which suggests that the former is an effective method to estimate the inhibition efficiency of inhibitors.

scholarly journals Corrosion Behaviour of High-Strength Al 7005 Alloy and Its Composites Reinforced with Industrial Waste-Based Fly Ash and Glass Fibre: Comparison of Stir Cast and Extrusion Conditions

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3929
Author(s):  
Praveen Kumar Swamy ◽  
Shantharaja Mylaraiah ◽  
Manjunath Patel Gowdru Chandrashekarappa ◽  
Avinash Lakshmikanthan ◽  
Danil Yurievich Pimenov ◽  
...  
Keyword(s):  
Fly Ash ◽  
Corrosion Rate ◽  
Electrochemical Impedance ◽  
Corrosion Behaviour ◽  
Research Work ◽  
Glass Network ◽  
High Strength ◽  
Stir Casting ◽  
Extrusion Process ◽  
Industrial Wastes

The stringent demand to develop lightweight materials with enhanced properties suitable for various engineering applications is the focus of this research work. Industrial wastes such as fly ash (FA) and S-glass-fibres (GF) were used as reinforcement materials for high-strength alloy, i.e., Al 7005. Stir casting routes were employed for fabricating the four samples, Al 7005, Al 7005 + 5% GF, Al 7005 + 6% FA and Al 7005 + 5% GF + 6% FA. The extrusion process with different extrusion ratios (ER: 5.32:1, and 2.66:1) was used to examine the properties of all four samples. Extruded samples with ER: 5.32: 1 resulted in equiaxed grains with refined structure compared to stir casting parts. The effect of the extrusion process and the addition of reinforcements (GF and FA) on the gravimetric, electrochemical, and electrochemical impedance corrosion behaviour of Al 7005 composites in 1M HCl (Hydrochloric acid) solution were investigated. The results of all three corrosion methods showed that Al 7005 + 6% FA exhibited higher corrosion resistance. Corrosion rate of Al 7005, Al 7005 + 5% GF, Al 7005 + 6% FA and Al 7005 + 5% GF + 6% FA is found equal to 3.25, 2.41, 0.34, and 0.76 mpy, respectively. The FA particles remain inert and act as a physical barrier with corrosive media during the corrosion test. GF undergoes fibre degradation or disrupts the continuity of the glass network as a result of fibre leaching, which increases the corrosion rate in the sample. The gravimetric study showed that the corrosion rates decreased with an increase in extrusion ratio, which might be due to corrosion passivation increases and improved properties. The scanning electron microscopy reveals that corrosion fits, flakes and micro-cracks were observed more in the as-cast composites than that of extrusion composites, promoting the corrosion rate.

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