The Influence of Different Gas Welding Flame on Corrosion Behavior of the Carbon Steel’s Heat Affected Zone in Seawater

The influence of different flame of gas welding on corrosion behavior of the carbon steel’s heat affected zone in seawater were studied by the weight-loss method, electroanalytical chemistry method and surface and microstructure observation. The result indicate that when gas welding the carbon steel, the corrosion rate of the heat affected zone under the influence of mild carbonizing flame is 0.1252[g／(m2•h)], in contrast, the corrosion rate of that under the influence of neutral flame is 0.1025[g／(m2•h)]; the order of corrosion current shows as follows: Imild carbonizing flame>Ineutral flame>Ibase metal; the order of measured corrosion potential as follows: Ebase metal>Eneutral flame>Emild carbonizing flame. Compared with the base metal, the heat effected zone are more likely to corrosion, corrosion resistance of the sample under mild carbon flame are the worse.

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Dissolution of chromium in sulfuric acid

Journal of the Serbian Chemical Society ◽

10.2298/jsc0211777d ◽

2002 ◽

Vol 67 (11) ◽

pp. 777-782 ◽

Cited By ~ 8

Author(s):

Dragutin Drazic ◽

Jovan Popic

Keyword(s):

Corrosion Rate ◽

Room Temperature ◽

Corrosion Potential ◽

Analytical Data ◽

Electrochemical Corrosion ◽

Spectrophotometric Analysis ◽

Weight Loss Method ◽

Loss Method ◽

Anomalous Dissolution

By combining electrochemical corrosion rate measurements and spectrophotometric analysis of the electrolyte it was shown that at room temperature chromium dissolves in deaerated 0.1M Na2SO4 + H2SO4 (pH1) solution as Cr(II) and Cr(III) ions in he ratio Cr(II):Cr(III)?7:1. This process was stable over 4h without any detectable change. The total corrosion rate of chromium calculated from the analytical data is about 12 times higher, than that determined electrochemically by cathodic Tafel line extrapolation to the corrosion potential. This finding was confirmed by applying the weight-loss method for the determination of the corrosion rate. This enormous difference between these experimentally determined corrosion rates can be explained by the rather fast, "anomalous" dissolution process proposed by Kolotyrkin and coworkers (chemical reaction of Cr with H2O molecules) occurring simultaneously with the electrochemical corrosion process.

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

Jurnal Teknologi ◽

10.11113/jt.v58.1552 ◽

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.

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Corrosion Behavior of a Nickel-Base Dental Casting Alloy in Artificial Saliva Studied by Weight Loss and Polarization Techniques

Frontiers in Dentistry ◽

10.18502/fid.v16i1.1104 ◽

2019 ◽

Author(s):

Elnaz Moslehifard ◽

Mahsa Moslehifard ◽

Sanaz Ghasemzadeh ◽

Farzad Nasirpouri

Keyword(s):

Weight Loss ◽

Corrosion Rate ◽

Corrosion Behavior ◽

Base Alloy ◽

Artificial Saliva ◽

Ph Values ◽

Significant Difference ◽

Weight Loss Method ◽

Loss Method ◽

Nickel Base

Objectives: Nickel-chromium (Ni-Cr) base dental alloys with desirable properties have been employed in prosthodontics for years. Corrosion behavior of a Ni-Cr base alloy in artificial saliva with different pH values is determined in this work. Materials and Methods: Corrosion behavior of Ni-Cr alloy was studied using weight loss described by corrosion rate (CR) in mils per year (mpy) and potentiodynamic polarization described by corrosion potential (CP) in mV and current density (CD) in mA/cm2 in artificial saliva with different pH. Surface morphology was studied using scanning electron microscopy (SEM). Statistical difference was assessed using one-way ANOVA and post-hoc Tukey's honestly significant difference (HSD) test with a difference significance of 95%. Results: In weight loss method, CR was 71.95±3.40, 17.26±1.03, 8.92±0.35, and 6.93±0.54 mpy at pH values of 2.5, 5, 7, and 9, respectively. CR obtained at pH of 2.5 was significantly different than that in other groups, but those obtained at pH of 5, 7, and 9 were not significantly different. In the polarization method, CP values were significantly different. CD measured at pH of 2.5 and 5 was significantly different than the rest of pH values (P<0.05). CRs at pH of 7 and 9 were not significantly different. SEM exhibited the formation of preferential sites of corrosion attacks influenced by pH. Conclusions: Both techniques revealed consistent results. Corrosion resistance increases as pH increases towards less acidic conditions. In more acidic saliva, the corrosion rate is greater. The less acidic saliva leads to formation of a more stable passive film on Ni, and the dissolution of Ni decreases, leading to lower CRs.

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EFFISIENSI INHIBISI INHIBITOR EKSTRAK DAUN TEH (Camelia sinensis) TERHADAP BAJA St-37 DALAM MEDIUM ASAM DAN GARAM

Jurnal Katalisator ◽

10.22216/jk.v1i1.1407 ◽

2016 ◽

Vol 1 (1) ◽

Author(s):

Yuli Yetri ◽

Desi Mita Sari ◽

Sri Handani

Keyword(s):

Weight Loss ◽

Corrosion Rate ◽

Corrosive Medium ◽

Corrosion Current ◽

Chloride Medium ◽

Weight Loss Method ◽

Optical Photograph ◽

Loss Method ◽

Tea Leaf ◽

Control Corrosion

Telah dilakukan penelitian untuk mengendalikan laju korosi baja St-37 dalam medium asam klorida dan natrium klorida menggunakan inhibitor ekstrak daun teh (Camelia sinensis). Metode weight loss dan metode potensiodinamik untuk menentukan laju korosi, dalam medium HCl 3 % dan NaCl 3 %, dengan konsentrasi inhibitor yang ditambahkan bervariasi mulai dari 1 % hingga 10 % dengan perendaman selama empat hari. Hasil penelitian menunjukan bahwa laju korosi berkurang dengan meningkatnya konsentrasi inhibitor yang ditambahkan, Peningkatan konsentrasi inhibitor diikuti juga dengan meningkatnya nilai effisiensin inhibisinya. Nilai efisiensi terbesar 86,3 % dengan penambahan konsentrasi inhibitor 10 % untuk medium korosif HCl dan dengan konsentrasi yang sama untuk NaCl mencapai 92,0%. Analisis morfologi permukaan dengan foto optik memperlihatkan permukaan baja dengan penambahan ekstrak daun teh mengalami korosi lebih sedikit dibandingkan dengan tanpa inibitor. Hal ini menunjukan bahwa inhibitor ekstrak daun teh sangat efisien untuk mengendalikan laju korosi dalam medium korosif HCl dan NaCl. A research to control corrosion rate of St-37 steel in acid chloride and sodium chloride medium using tea leaf (Camellia sinensis) extract inhibitor has been done. The method used is potentiodynamic to see the value of the corrosion current and weight loss method for corrosion rate.. Corrosive medium used were HCl 3% and NaCl 3%. The concentration of the extract used range from 1%-10% and the immersion time is four days. The results showed that the corrosion rate was greatest in the corrosive medium without addition of inhibitors, whereas the corrosion rate decreases with the addition of inhibitors, it is also evident from the results of the Tafel plot shows Icor impairment. The greater the concentration of inhibitor that is used the lower the corrosion rate. Greatest efficiency values both for medium corrosive obtained at inhibitor concentrations of 10%, 86,3% in HCl and 92% in NaCl. This shows that tea leaves extract inhibitor is very efficient in controlling the rate of corrosion in HCl and NaCl medium. From the optical photograph analysed on the surface morphology of St-37 steel showed that the addition of tea leaf extract suffered less corrosion.

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Microstructural change and corrosion variation of SAPH440 steel induced by pre-deformation

Materials Express ◽

10.1166/mex.2019.1546 ◽

2019 ◽

Vol 9 (6) ◽

pp. 610-615

Author(s):

Shuo Weng ◽

Hongchang Cai ◽

Lihui Zhao ◽

Songlin Zheng

Keyword(s):

Electron Microscopy ◽

Tensile Elongation ◽

Corrosion Current ◽

Open Circuit ◽

Corrosive Solution ◽

Microstructure Observation ◽

Transmission Electron ◽

Weight Loss Method ◽

Corrosion Susceptibility ◽

Loss Method

The influence of microstructural variation on corrosion of SAPH440 steel induced by pre-deformation has been investigated in the corrosive solution. The microstructure observation was carried out by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The corrosion was characterized by weight loss method (WLM), open circuit potential (OCP) and potentiodynamic polarization curve (PPC) measurements. The results show that compared to the as-received specimens, the corrosion potential moves to the negative direction and corrosion current density increases after pre-deformation. The corrosion susceptibility is enhanced by the pre-deformation behavior, which is attributed to the increase in dislocation density with the increasing tensile elongation.

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Effects of Surfactant on Corrosion Behavior of Carbon Steel in Simulated Crude Oil

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1115.223 ◽

2015 ◽

Vol 1115 ◽

pp. 223-225

Author(s):

Mohammad Zakaria ◽

Suryanto ◽

Irfan Hilmy

Keyword(s):

Carbon Steel ◽

Corrosion Rate ◽

Crude Oil ◽

Enhanced Oil Recovery ◽

Corrosion Behavior ◽

Oil Recovery ◽

Oil And Gas ◽

Uniform Corrosion ◽

Weight Loss Method ◽

Loss Method

Enhanced Oil Recovery (EOR) is a technique used in oil and gas industries to increase the amount of crude oil production by injection of brine, a mixture of surfactant, water and seawater. As the results, crude oil contains brine which is corrosive. Surfactant is used to lessen the corrosion effect in addition to increase flowing of oil. In this study, the effect of surfactant on corrosion behavior of carbon steel in simulated enhanced oil recovery crude was investigated. Autoclave machine was used to perform corrosion experiment in the oxygen free environments. Corrosion rate was measure using weight loss method. The results show that surfactant reduces corrosion rate of carbon steel from 0.061 mm/y to 0.042 mm/y and the corrosion type on carbon steel was uniform corrosion.

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Potensi Ekstrak Daun Pepaya sebagai Inhibitor Korosi dalam Media Asam Klorida pada Baja ST37

REACTOR: Journal of Research on Chemistry and Engineering ◽

10.52759/reactor.v2i2.37 ◽

2021 ◽

Vol 2 (2) ◽

pp. 48

Author(s):

Dwi Kemala Putri ◽

Addin Akbar

Keyword(s):

Hydrochloric Acid ◽

Corrosion Rate ◽

Potentiodynamic Polarization ◽

Steel Surface ◽

Corrosion Current ◽

Polarization Method ◽

Immersion Method ◽

Weight Loss Method ◽

Loss Method

Corrosion is a decrease in the quality of a metal material caused by a reaction with the environment. Reducing the corrosion rate on steel can be done by adding an inhibitor. Papaya leaf extract (Carica papaya.L) can be used as a corrosion inhibitor by immersion method. The effect of inhibitor on corrosion rate had been studied using weight loss method, potentiodynamic polarization method, and observation of steel surface using photooptic. It was found that corrosion rate decrease with increase concentration of papaya leaves extract. The highest inhibiton efficiency is 87.8% in 0.2 M hydrochloric acid with 2% concentration of papaya leaves extract. Potentiodynamic polarization method showed that papaya leaves extract decrease corrotion current. Inhibiton efficiency reached 81.58% in 2% extract concentration in which corrosion current decrease from 0.0266 mA/cm2 to 0.0049 mA/cm2. Analysis of photooptic showed that there is difference on steel surface corroded in hydrochloric acid with inhibitor and without it.

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Corrosion Behavior for Casing in Producing Well with Water Injection Technology during Long-Term Service

Materials Science Forum ◽

10.4028/www.scientific.net/msf.993.1168 ◽

2020 ◽

Vol 993 ◽

pp. 1168-1173

Author(s):

Xin Sun ◽

Rong Li Nan ◽

Bo Zhao Shu ◽

Hang Wang ◽

Li Juan Zhu ◽

...

Keyword(s):

Corrosion Rate ◽

Corrosion Behavior ◽

Water Injection ◽

Injection Pressure ◽

Continuous Increase ◽

Oxygen Condition ◽

Weight Loss Method ◽

Loss Method ◽

Injection Technology

Corrosion leakage became serious due to cyclic sewage injection and continuous increase in water injection pressure. Corrosion behavior for N80 casing was studied during long-term service, using corrosion reaction kettle and weight loss method. The morphology and composition were characterized with laser confocal microscopy (LCM), scan electron microscopy (SEM) and energy disperse spectroscopy (EDS). These results showed that corrosion rate remained constantly at initial stage, and increased gradually, then sharply reached to 0.327mm/a at later stage, accompanying with inflection point under oxygen condition. Meanwhile, corrosion rate decreased significantly from 0.028mm/a to 0.020mm/a under oxygen-free condition. The corrosion of N80 steel was dominated by dissolved oxygen, and accelerated by chloridion. The micro-mechanism was suggested to be the transition of defect structure from crack with micron range to etch pit with millimeter range.

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Corrosion Behavior of Copper and Carbon Steel in Acidic Media

Baghdad Science Journal ◽

10.21123/bsj.11.4.1577-1582 ◽

2014 ◽

Vol 11 (4) ◽

pp. 1577-1582

Author(s):

Baghdad Science Journal

Keyword(s):

Carbon Steel ◽

Hydrochloric Acid ◽

Sulphuric Acid ◽

Corrosion Behavior ◽

Effect Of Temperature ◽

Acidic Media ◽

Corrosion Rates ◽

Weight Loss Method ◽

Acid Environment ◽

Loss Method

The corrosion behavior of copper and carbon steel in 1M concentration of hydrochloric acid (HCl) and sulphuric acid (H2SO4) has been studied. The corrosion inhibition of copper and carbon steel in 1M concentration of hydrochloric acid (HCl) and sulphuric acid (H2SO4) by Ciprofloxacin has been investigated. Specimens were exposed in the acidic media for 7 hours and corrosion rates evaluated by using the weight loss method. The effect of temperature (from 283 ºK to 333 ºK), pH (from 1to 6), inhibitor concentration (10-4 to 10-2) has been studied. It was observed that sulphuric acid environment was most corrosive to the metals because of its oxidizing nature, followed by hydrochloric acid. The rate of metal dissolution increased with increasing exposure time. Corrosion rates of carbon steel in the acidic media found to be higher.

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Electrochemical Characteristics of Lanthanum Hexaboride in the Environments Containing S2-

Materials Science Forum ◽

10.4028/www.scientific.net/msf.663-665.473 ◽

2010 ◽

Vol 663-665 ◽

pp. 473-476

Author(s):

Shu Qi Zheng ◽

Chang Feng Chen ◽

Rui Jing Jiang ◽

Dan Ni Wang

Keyword(s):

Partial Pressure ◽

Corrosion Behavior ◽

Current Density ◽

Corrosion Current Density ◽

Corrosion Potential ◽

Corrosion Current ◽

Lanthanum Hexaboride ◽

Electrochemical Characteristics

In the environment with H2S/CO2 or Na2S, the corrosion behavior of Lanthanum hexaboride (LaB6) was investigated by electrochemistry methods. The results indicated that the corrosion potential (Ecorr) and Rf of LaB6 increased as the partial pressure of H2S increased, while the corrosion current density (Icorr) decreased. In the environment containing Na2S, as the content of Na2S increased, the corrosion potential (Ecorr) and Rf of LaB6 decreased, while the corrosion current density (Icorr) increased. Thus, the addition of H2S into the environment with H2S/CO2 would inhibit the corrosion of LaB6; while in the environment containing Na2S, the increasing of the content of Na2S would accelerate the corrosion of LaB6.

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