Corrosion Rate Test Research Articles

Corrosion inhibitor behavior in typical car radiators

A minor breakdown of the cooling system will cause engine overheating. One of the factors causing the engine overheating is the crust on radiator of cooling system. Based on the problem, therefore, corrosion on the cooling system, especially radiator, should be controlled. There are some methods in controlling the corrosion; one of them is the inhibitor treatment. The research aims to know the corrosion mechanism, the corrosion type, and the kind of inhibitor that produces the lowest corrosion rate. The tool used to measure the chemical composition of the radiator is spectrometer, while microscope optic is used to know the radiator corrosion type. The corrosion rate testing is used three electrode cells according to tafel extrapolation method. The results of the test of the nitric acid inhibitor treatment with the addition of various methods showed that the most optimal result is on the addition of nitric acid inhibitor by 5%. It is proven by the decrease of corrosion rate from 0.002207 mmpy to 0.0171 mmpy.

Efficiency of Ketapang (Terminalia catappa L.) Leaves Tannin Extract as Organic Inhibitor Against Corrosion Rate of Iron Metal in Seawater

The research is about effect of immersion time and mechanical properties on the rate of corrosion of ferrous metals by the addition of Ketapang (Terminalia catappa L.) leaf extract as an organic inhibitor in the seawater environment. In this study, ketapang leaf extract was used as a natural inhibitor to inhibit the rate of corrosion of ferrous metals. This inhibitor is used on iron metal plates which are immersed in corrosive media, namely sea water with variations in the composition of the inhibitors used at 0; 10% V; 20% V, and 40% V, with immersion time of 3 and 6 days. The characterizations tested included measurement of density, corrosion rate, inhibitor efficiency, and hardness testing using the Vickers method. From the measurement results, the density value decreases with the addition of the concentration of the inhibitor both on immersion 3 days and 6 days. The value of hardness increases with increasing composition of the inhibitor. The optimum hardness value is 165.03 N/m2 with immersion time of 6 days at an inhibitor concentration of 40% and a minimum hardness value of 145.603 N/m2 on immersion 6 days with no inhibitor. The smallest corrosion rate was obtained by samples with a composition of 40% inhibitor of 2.77 mpy with immersion time of 3 days and 1.33 mpy with immersion time of 6 days. And the efficiency value of Ketapang leaf extract inhibitors reached 47.01 % in the composition of 40% in the seawater environment with immersion time of 6 daysketapang leaves

Microstructure, mechanical and corrosion properties of the 50%Ni-47%Ti-3%Cu shape memory alloy

in this study, the mechanical, microstructure and corrosion properties of Nickel-Titanium-Copper shape recovery alloys were investigated. The alloy was prepared by the powder metallurgy method, where powders of 50% Titanium, 47 % Nickel and 3% Cupper were mixed and cold compacted at (600,700 and 800) MPa to form cylindrical samples of (11mm diameter × 16.5mm length) and (11mm diameter ×5 mm length). After compaction process the specimens had more green strength for handling. The samples were subsequently sintered at a temperature of (850,900 and 950) °C for a period of 5 hours in an electric vacuum tube furnace. Multiple tests were conducted on the alloys including porosity measurements, scanning electron microscopy (SEM), compression strength, shape memory effect and corrosion rate test. The results indicate improvement in compression strength and shape memory effect with low sintering temperature and high compacting pressure as well as reduction in the corrosion rate.

Synergistic Effect of O2 and H2S on the Corrosion Behavior of N80 Steel in a Simulated High-Pressure Flue Gas Injection System

The aim of this work was to understand the synergistic effect of O2 and H2S on the corrosion behavior of N80 steel in a simulated high-pressure flue gas injection system. Weight loss measurements show that the presence of O2 and an increase in temperature significantly accelerated the general corrosion rate of the N80 steel. We calculated a gray relational grade between different impact factors and the general corrosion rate from the results of an orthogonal experimental corrosion rate. The grade ranking of impact factors was: O2 concentration (0.817) > temperature (0.706) > total pressure (0.689) > H2S concentration (0.665) > CO2 concentration (0.517). Surface characterization of corrosion scales was done using scanning electron microscopy, energy-dispersive spectroscopy, x-ray powder diffraction, and 3D optical microscope analysis. The results show that in the O2-H2S-CO2-H2O coexistence system the products were composed mainly of FeCO3, FeS, Fe2O3, Fe3O4, and elemental sulfur. The results of the corrosion rate test and the characterization show that the presence of O2 greatly accelerated the corrosion process and changed the corrosion mechanism. Elemental sulfur, which was generated by the reaction between the H2S and the O2, participated in the corrosion process of the N80 steel. It could be considered that the synergistic effect of O2 and H2S accelerated the corrosion of the N80 steel. In addition, the porous structures of the corrosion scales and the severe local pits show that the high content of O2 inhibited the formation of FeCO3 and aggravated the corrosion of N80 steel.

Effect of Chromate Inhibitor on the Corrosion Rate of API 5L Grade B Steel Pipe in the Injection Water

Corrosion inside the injection water pipe occurs from the Central Injection Facility Station to the wellhead. One way to reduce the rate of corrosion is to add inhibitors. This research is looking for the effect of variations in the concentration of the sodium chromate inhibitor (Na2CrO4) on the corrosion rate of API 5L grade B pipes used in the oil industry, especially in injection water fluids. For comparison, a corrosion rate test was carried out on a 3.5% NaCl solution. The study used an NPS 4 SCH 40 pipe with an outer diameter of 4.5 in (114.3 mm) with a thickness of 0.237in (6.02mm). The concentration parameter of the Sodium Chromate inhibitor used is 0.1; 0.3; 0.5; 0.7 and 0.9%. The study used a corrosion rate test using the potentiodynamic polarization method. The results showed the pipe corrosion rate in the injection water fluid was 0.3307 mpy, and the pipe corrosion rate in the 3.5% NaCl solution was 0.4960 mpy. The addition of chromate inhibitors succeeded in decreasing the corrosion rate. The maximum condition is achieved with the addition of 0.9% inhibitor. In this condition, the corrosion rate of the pipe in the injection water solution is 0.2175 mpy and the corrosion rate of the pipe in the 3.5% NaCl solution is 0.3218 mpy.

Pengaruh Rapat Arus Proses Continuous Hard Anodizing Elektrolit (H2SO4) terhadap Laju Korosi Pipa Aluminium 6061 dengan Pengujian Kabut Garam

Anodizing is an electro-chemical process used to coat metal surfaces with a stable oxide layer. The function of this oxide layer is to increase corrosion resistance. The purpose of this study is determine the effect of variations in current density on the continuous hard anodizing process carried out in sulfuric acid electrolyte solution (H2SO4) on the corrosion rate of aluminum alloy 6061. Corrosion rate testing is carried out through salt fog testing. The values of the current variation used are 1 A/dm2; 2 A/dm2; 3 A/dm2; 4 A/dm2; and 5 A/dm2. Statistical calculations using the analysis of variance proved the current density in the anodizing process has a significant effect on the corrosion resistance of the anodizing workpiece. Corrosion testing provides information that the highest corrosion rate is an anodizing workpiece with a current density of 1 A/dm2, which is 125.6861 mdd, then 2 A/dm2 of 104.33333 mdd. The lowest corrosion rate value obtained at the use of current density 3 A/dm2, that is 51,8083 mdd. Meanwhile, the use of current density of 4 A/dm2 has a slightly higher corrosion rate compared to the use of current density of 3 A/dm2, which is 86.5444 mdd. Furthermore, the use of current density of 5 A/dm2 has the highest decay rate, so that the formed oxide layer will be damaged, as seen from the higher corrosion rate of the material, which is 100.8361 mdd.

Preparation of Calcium Magnesium Acetate Snow Melting Agent Using Raw Calcium Acetate-Rich Made from Eggshells

A large number of discarded eggshells bring serious environmental pollution and waste of resources. To solve this problem, raw product of calcium acetate was prepared from waste eggshell by the ultrasonic assisted neutralization method, thus, the best material ratio of calcium and magnesium, a non-chloride environment-friendly snow melting agent, which took calcium acetate as raw material by optimizing the experimental conditions, was determined. In this paper, the eggshell powder with a recovery rate of 90% was firstly obtained through the separation of eggshells and shell membrane; then, calcium acetate was prepared with a high yield of about 95.29% using ultrasonic neutralization treatment and suction filtration, and its properties including the calcium content, pH, moisture determination, sulfate, chloride, etc. were characterized with satisfaction according to the national standard, China (GB/T 23851-2009, China), the U.S. Pharmacopeia and related literature. Furthermore, different ratios of calcium and magnesium products were prepared and its properties on the pH, freezing point, dissolution rate, ability to melt snow and ice, concrete corrosion rate, carbon steel corrosion rate and plant salt tolerance test, were compared with commercially available snow melting agents. The best snow melting agent with calcium to magnesium ratio of 5:5 was picked over to be a substitute for the chlorine salt snow melting agent which can reduce the environmental pollution by discarded eggshells caused. The results obtained also provided a new theoretical basis and credible experimental data for the preparation of environmentally friendly snow melting agents.

A Study on the Corrosion Inhibition Effect of Hexamethylene Tetramine on Welded API 5L X70 Steel in E10 Fuel Ethanol Environment

The inhibition effect of hexamethylenetetramine (HT) in E10 environment for the corrosion protection of welded API 5L X70 pipeline steel was examined using immersion tests. Welded samples of API-5L X70 steel of dimension 30 mm x 15 mm were immersed into E-10 fuel ethanol containing hexamethylenetetramine concentration of (0.2, 0.4, 0.6, 0.8) g and the control for a minimum of 4 days and a maximum of 28 days. Analysis was done using mass loss, corrosion rate, inhibitor efficiency and ANOVA test. From the mass loss and corrosion rate analysis, it was observed that 0.2g HT, which was the lowest concentration of inhibitor, proved best for inhibiting corrosion at 24 days.

Effects of variations in the addition of SiCp filler to corrosion rate of metal matrix composites (MMCs) Al-Cu-Mg/SiCp

We study of effecs Al-Cu-Mg/SiCp Metal Matrix Composites (MMCs) with a matrix composition of 4.4 wt% Cu, 1.8 wt% Mg with SiCp fillers were varied (3.4; 3.7 and 4.0) wt% and the remaining Al. SiCp is mixed into Al-Cu-Mg heated at 900oC, then stir casting is carried out at 250 rpm for 10 minutes. Then cooling is carried out to room temperature. After cold, heat treatment is given and continued testing. The SEM-EDX and XRD test results showed that the increasing SiCp content, the tendency for SiCp and Mg bonds to form the Mg2Si phase increased, making the sample items enlarge and appear coarser. While the corrosion rate test of increasing SiCp in the Al-Cu-Mg matrix makes Al-Cu-Mg/SiCp samples tend to be more corrosion resistant. The event of declining corrosive properties is due to SiCp particles occupying grain boundary areas replacing O2 (which provides corrosive properties) that are trapped in the sample during the cooling process.

Investigation of the stress corrosion cracking behavior in annealed 5083 aluminum alloy sheets with different texture types

Al–Mg alloys are commonly employed for anti-corrosion parts in marine and rail vehicles. However, the corrosion resistance of these alloys is affected by the alloy microstructure. In this study, 5083 aluminum alloy sheets with different recrystallized textures (a low-intensity texture, a cube-based texture, and a brass-based texture) were obtained by cold rolling and annealing. The stress corrosion cracking and short crack propagation behavior were investigated based on the microstructural characterization, intergranular corrosion, electrochemical corrosion, and slow strain rate testing. The results showed that the tested samples exhibited large differences in stress corrosion properties, although they had a similar resistance to intergranular corrosion. The sample dominated by the brass texture exhibited the best resistance to stress corrosion cracking (SCC) with an ISSRT of 11.7%, while the sample with the low-intensity texture exhibited the worst resistance to SCC with an ISSRT of 29.7%. Moreover, the stress corrosion crack in the sample dominated by the brass texture propagated along a more tortuous path. The crack was deflected at brass texture grains, which was attributed to the combined effects of the relatively large twist angle between the grain boundaries of brass grains and neighboring grains and the low grain boundary energy configuration of {011} orientation grains.

Corrosion of Carbon Steel in Oxygen and NaCl Concentration Cells: the Influence of Solution Temperature and Aeration

Corrosion rate tests were carried out on carbon steel under concentration cells conditions of oxygen and sodium chloride. The effect of aeration in one compartment on the corrosion rate of both coupled metals was determined. In addition, the effects of time and temperatures on the corrosion rate of both coupled metals and galvanic currents between them were investigated. Corrosion potentials for the whole range of operating conditions under concentration cell conditions were also studied. The results showed that under aeration condition, the formation of concentration cell caused a considerable corrosion rate of the Carbon steel specimens coupled in different concentrations of O2 and NaCl due to the galvanic effect. Aerating one compartment caused a noticeable increase in the corrosion rate of the coupled specimen in the other compartment due to the galvanic effect. Increasing temperature caused unstable trends in the free and galvanic corrosion potentials. Increasing the temperature led to an increase in the corrosion rate for both metals.

The effect of Lead (Pb) Hot dipping on seawater corrosion rate in ASTM A36 Steel

Corrosion attacks are a scourge on offshore industrial structures. The hot dipping method is a common method used in protecting submerged material from corrosion attacks. The main objective of this study was to investigate the effect of variations in hot dipping time in Lead (Pb) on corrosion attack by performing corrosion rate test, weight loss measurement, microstructure analysis and fatigue test. The results revealed that the longer the hot dipping was carried out there was a decrease in the value of corrosion rate and weight loss of ASTM A36.

Influence of red mud on mechanical and durability performance of self-compacting concrete.

Red mud is a hazardous waste material produced during alkaline leaching of bauxite in the Bayer process. This study proposed the use of red mud to replace fly ash in self-compacting concrete (SCC) and the influences of red mud on fresh and hardened properties, and durability performances of SCC were studied. The fresh concrete results show that red mud had a slight negative impact on the fresh properties of SCC. The hardened concrete results show that the mechanical strength of concrete increased with increasing of red mud content. The half-cell potential test results indicated that red mud had a significant effect on restraining the corrosion process in SCC. Compared to the control sample, the red mud samples suffered less corrosion. Cracks associated with corrosion of reinforcement were observed in RMC0 and RMC100 samples after 28 day accelerated corrosion test. The ICP-MS results showed that there's no significant difference in metal elements among the solutions regardless the red mud content in concrete.The relative corrosion rate test results suggested that red mud can suppress the corrosion current. The SCC samples consisting 75% red mud performed the best resistance to corrosion according to the results of half-cell potentials and mass loss of rebar.

Welding current effect of welded joints of base metal st37 on characteristics: corrosion rate and hardness

This study aims to determine the effect of welding current on corrosion rate and hardness on welded joint, Heat Affected Zone (HAZ) and base metal of steel grade st37. Welding is the process of metal attachment by dilution through heating. Due to the heat of the metal around the weld will undergo thermal cycles that cause metallurgical changes in microstructure, which will affect corrosion rate and the mechanical properties such as hardness. Weld joints are one of the critical parts of a structure. The weld joints that get excessive friction will be worn fast and corrosion rate higher than the base metal. The steel grade st37 strips are treated with welding current variations of 75, 85, and 95 Amperes. The method used for corrosion rate testing is ASTM G31-72 standard where this test is based on weight loss test and corrosion solution used NaCl solution with 3% concentration. The results showed that the highest average corrosion rate of 0.10516 mmpy occurred in the strip welded to the current of 95 Ampere, followed by 85 Ampere at 0.06772 mmpy, and the current of 75 Ampere was 0.06152 mmpy. Testing of material hardness at current 75, 85, and 95 Amperes shows that the highest hardness value occurs in weld metal area with 75 Ampere with average hardness at 74.00 HRC. Current selection to during welding process has shown a significant effect on corrosion rate and hardness on the welded joint (weld metal).

Copper-deposited aluminum anode for aluminum-air battery

For Al-air batteries, it is important to develop efficient and economical anodes. In this study, the effect of aluminum anodes treated with copper by chemical and electrochemical process to battery performance is investigated. The surface characterization of this electrode is performed with a scanning electron microscope. Electrochemical impedance spectroscopy and anodic polarization techniques are used. The hydrogen gas evolution and corrosion rate tests, the constant-voltage discharge tests, and the galvanostatic anodic dissolution tests are carried out. The anode utilizations are calculated. It is seen that the copper improves the anode efficiency by promoting the dissolution of aluminum according to battery reaction. However, it protects the aluminum from corrosion reaction by forming a barrier film without any restriction of battery reaction. It is understood from this work that the most efficient, economical, and practical method for copper deposition to electrode is the electrochemical deposition of copper. Furthermore, the 7075 alloy (Alloy/Cu) is more stable for both the electrochemical and chemical deposition process.

STUDI EXPERIMENTAL FATIK KOROSI ALUMINIUM PADUAN 7075-T6 PADA LINGKUNGAN 3,5% NaCl DENGAN INHIBITOR Na2CrO4

AA7075-T6 aluminum alloy is a material that widely used in the aircraft industry because aluminum as a lightweight metal, good machinability, good corrosion resistance and good castability and non-magnetic metals. Aluminum also has high tenacity, is easy to form and is easy to connect. Aluminum has good resistance to corrosion, however aluminum has effect to corrosion if it is on corrosive environment including AA7075-T6 aluminum alloy which used in the aircraft industry. Inhibitor is used to control a corrosion. The aims of these researchs were to investigate the effect of inhibitors on corrosion rates and the rate of fatigue crack corrosion propagation on AA7075-T6 aluminum alloys. This research is used Na2CrO4 inhibitors with variety of concentrations of 0.1%, 0.3%, 0.5% and 0.7% added to 3.5% NaCl solution. Corrosion rate test is used a method of potential dynamic polarization. Corrosion fatigue testing is carried out with constant amplitude at a frequency of 10 Hz and a voltage ratio (R) 0.1. Specimens were used cracked specimen centers (CCT) on orientation in the direction of rolling. The supporting data of the research were the mechanical properties of the material included optical microstructure observation, tensile testing and hardness testing. The results have shown that the optimal concentration of Na2CrO4 inhibitors was achieved at 0.5% which was characterized by a decreasing in corrosion rate and slower corrosion rate of fatigue cracking.

The Effect of Current Densities in Zinc Electroplating Process on Mild Steel for Soil Water Environment Application

For more environmental friendly study, commonly undesired natural process which is corrosion will present. Thus, in this century there is a serious effort in ongoing analysis in order to prevent this phenomenon occurring. The challenge of corrosion in manufacturing and domestic sector is enormous. Thus, corrosion can be defined as the deterioration and destruction of a material because of reaction with the environment. Replacing a corroded pipeline can cost about $643,000 per kilometer. The application of the traffic sign or a road sign that embedded in soil usually can withstand for two to three years until it will corrode and then fracture. The main objectives of this study is to increase the protection on the surface of the materials towards corrosion and to improve the appearance of the product or serves as an effective undercoat for paints which can reduce the cost of using expensive material by using the other method; electroplating process. The samples were plated with zinc at 2, 4 and 6 A/dm2 for 20 minutes for every sample. Then, the samples were immersed in the artificial soil solution for 30 days, then the testing to measure the corrosion rate, phase analysis, morphological analysis and hardness test were conducted. From all the tests, sample with 6 A/dm2 got the best results with 5.2059 mpy and 80.6 HV hardness strength. It is because by increasing the current density, the thickness will then increase the zinc plating will not easily peel off and attack by corrosive agent.

Effect of Ag Content and β-PbO2 Plating on the Properties of Al/Pb-Ag Alloy

Due to the excellent electrical conductivity and mechanical properties, Al/Pb-Ag alloy has a great potential to be used as an alternative anode for zinc electrowinning. In this work, the effects of Ag content and surface plating with β-PbO2 on the anodic behavior and reaction kinetics were investigated by cyclic voltammetry (CV), anodic polarization curves, electrochemical impedance spectroscopy (EIS) and corrosion rate test. The phase composition and microscopic morphology of the anode oxide layers after electrolysis were observed by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The results indicate that high content of silver and electroplating β-PbO2 layer can increase the oxygen evolution activity, electrocatalytic activity and corrosion resistance of the anodes. Al/Pb-0.75%Ag plating β-PbO2 has the lowest oxygen evolution overpotential followed by Al/Pb-0.3%Ag plating β-PbO2, Al/Pb-0.75%Ag and Al/Pb-0.3%Ag. Besides, high content of silver is more beneficial to improving corrosion resistance compared with electroplating β-PbO2 on anode. In addition, the phase composition of four anodes layer are mainly composed of α-PbO2, β-PbO2, Pb and PbO.

EXTRACT OF COCOR BEBEK (KALANCHOE PINNATA) AS A CORROSION INHIBITOR

In this study, Cocor Bebek leaves (Kalanchoe pinnata) extract is studied for metal corrosion inhibitor. 10.3 kg of K. Pinnata leaves produce concentrated extract of methanol, n-hexane and ethyl acetate as much as 65.7442, 36.1452, and 15.2711 g respectively. The concentrated extracts were then used to determine the rate of corrosion. Corrosion rate test showed that extract of ethyl acetate can reduce corrosion rate of carbon steel in NaCl 3.5% from 2.954 mpy to 0.963 and 0.923 mpy using 500 ppm and 1000 ppm of extract consecutively. Corrosion rate of Cocor Bebek extract at addition of 500 ppm ethyl acetate in the solution of NaCl 3.5% is decreasing immediately. It was found that the carbon steel corrosion rate decrease as much 4.857 for 6 hours and continuously shows sharp decline until 24 hours of corrosion time. Corrosion rate is slowly decreasing till reach 1.694 mpy at corrosion time of 168 hours.

Pengaruh Korosi terhadap Kekuatan Tarik Macaroni Tubing P110 1.900" x 4.19 lbs/ft

<em>Macaroni Tubing P110 1.900″ x 4.19 lbs/ft which applicated at Snubbing and Oil and Gas industry, exposed to Corrosive fluids such as NH4Cl, KCl and Sea Water. Macaroni Tubing P110 1.900″ x 4.19 lbs/ft also has mechanical treatment especially Tensile force. That’s why effects of NH4Cl, KCl and Sea Water fluid to Corrosion Rate and Tensile strength Macaroni Tubing P110 1.900″ x 4.19 lbs/ft shall be known. Starting from those issue, Immersion corrosion testing using NH4Cl, KCL and sea wáter instruments is conducted, and Tension testing is performed to the material after exposed to those corrosive fluids. Immersion corrosion testing method is used to analyze corrosion rate and Tension testing is used to analyze the tensile strength. The result shown that the fastest Corrosion rate is material which immersed to 6% NH4Cl with average corrosion rate value 0,210 mm/year. In second position is material which immersed to 3% KCl with average corrosion rate value 0.132 mm/year and the latest is material which immersed to sea water with average corrosion rate value 0.095 mm/year. Meanwhile, tensile strength test shown 676.53 Mpa for Raw Material specimens, 664.19 Mpa for specimens which immersed to 3% KCl, 653.51 Mpa for specimens which immersed to 6% NH4Cl and 669.55 Mpa for specimens which immersed to sea water. From those three specimens which immersed to corrosive fluid shown tensile strength decreased than Raw Material tensile strength and Specimen which immersed to 6% NH4Cl shown the biggest value.</em>