Influence of Surface Roughness and Paint Coating on Corrosion Rate

<p>The technology of paint and its application develop fast, driven by the increasing cost of energy, raw material and labors. In this study, paint was used as a corrosion inhibitor on the surface of API 5L while saltwater is used as the corrosive media. The coating was varied for three different cases, i.e. primary coating only, primary and color coating as well as primary, color and glossy coating. Meanwhile, surface roughness was varied for 0.6, 0.7 and 0.8 μm. It is concluded that surface roughness and coating influence the corrosion rate. Smoother the surface and more coating layers lower the corrosion rate. Based on the study on API 5L steel, the lowest corrosion rate was obtained at 0.6 μm with 3 paint coatings (primary, color paint and clear/gloss)</p>

Download Full-text

Analytical solution for the lifetime of a spherical shell of arbitrary thickness under the pressure of corrosive environments: The effect of thermal and elastic stresses

Journal of Applied Mechanics ◽

10.1115/1.4050280 ◽

2021 ◽

pp. 1-25

Author(s):

Yulia G. Pronina ◽

Olga S. Sedova

Keyword(s):

Corrosion Rate ◽

Spherical Shell ◽

Stress Component ◽

Equivalent Stress ◽

Circumferential Stress ◽

Thermoelastic Stress ◽

Decisive Role ◽

Process Conditions ◽

Corrosive Media ◽

Arbitrary Thickness

Abstract The paper presents analytical solutions to initial boundary value problems of thermoelasticity with a priori unknown evolving boundaries. To be more precise, we consider a spherical shell of arbitrary thickness subjected to the internal and external pressures of corrosive media at generally different temperatures, with taking into account the mechanochemical effect and inhibition of corrosion process. Conditions under which the circumferential stress can serve as the equivalent stress are determined. It was found that the life of the shell was influenced by the competing effects of the pressures and temperatures on the corrosion rate and stress values, as well as by possible moving the location of the maximal stress. It was also concluded that the elastic stress component played a decisive role in the synergistic growth of the total thermoelastic stress and the corrosion rate.

Download Full-text

Wear and Corrosion of Wrought A6061 Aluminium Alloy in DOT3 Brake Fluid

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i2.9611 ◽

2018 ◽

Vol 7 (2.14) ◽

pp. 512 ◽

Cited By ~ 4

Author(s):

Olawale Ajibola ◽

Oladeji Ige ◽

Peter Olubambi

Keyword(s):

Corrosion Rate ◽

Test Method ◽

Alloy Sample ◽

Corrosive Media ◽

Chemical Corrosion ◽

Brake Fluid ◽

Wear And Corrosion ◽

Cast Specimen ◽

Fluid Environment ◽

A6061 Alloy

The twofold impact of wear and corrosion on wrought A6061 alloy in hydraulic DOT3 brake fluid environment was studied. The wear studies were performed on the samples using a developed wear-jig. Weight loss corrosion test method was used to determine the corrosion rate of the wrought A6061 alloy samples immersed in the brake fluid for a total of 1680 hours. From the results of wear tests carried out on the A6061 alloy sample with brake oil, the highest wear value of 5.24x10-7 mg/mm2/cycle (approx.) was obtained from 6 N (approx) force after 130 minutes. The wrought A6061 alloy material demonstrated the highest corrosion rates nearly 3.0 x10-2 mg/mm2/yr within the early 168 hours of immersion in brake fluid. The result is practically lower than the corrosion rate of cast specimen in DOT3 brake oil or some other alloys immersed in other corrosive media that were previously reported in the literature. The results show that small amount of chemical corrosion is sufficient to cause and accelerate mechanical wear of the material in usage.

Download Full-text

Study on Permeability Coefficient of Different Bamboo/Fir Veneer Surface

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.311-313.1634 ◽

2011 ◽

Vol 311-313 ◽

pp. 1634-1637 ◽

Cited By ~ 2

Author(s):

Li Hong Yao ◽

Xi Ming Wang ◽

Ben Hua Fei

Keyword(s):

Surface Roughness ◽

Contact Angle ◽

Permeability Coefficient ◽

Phenolic Resin ◽

Chinese Fir ◽

Raw Material ◽

Important Indicator ◽

Veneer Surface ◽

Surface Permeability ◽

Analysis Models

Permeability coefficient is an important indicator of surface wettability and permeability, which influenced by the surface roughness. In this paper, bamboo and fir veneer as raw material, the contact angle of phenolic resin adhesives in different surface roughness of outer cuticle of bamboo, inner skin of bamboo, tight side of Chinese fir veneer and loose side of Chinese fir veneer were measured, and then use the software Spass non-linear fitting for permeability coefficient, and analysis of variance of the results by SAS software. The results show that permeability coefficient of four different kinds of surface variance analysis models are significantly, permeability coefficient of fir veneer is larger than bamboo surface; permeability coefficient of tight side of fir veneer is larger than loose side; permeability coefficient of inner skin of bamboo is larger than outer cuticle of bamboo. Permeability coefficients decrease first and then increased when mesh sandpaper increasing.

Download Full-text

Surface roughness of uncoated particleboards and its relation with the raw material, adhesive and climatic conditions

European Journal of Wood and Wood Products ◽

10.1007/s00107-009-0363-8 ◽

2009 ◽

Vol 68 (4) ◽

pp. 369-372 ◽

Cited By ~ 3

Author(s):

A. Rolleri ◽

E. Roffael

Keyword(s):

Surface Roughness ◽

Climatic Conditions ◽

Raw Material

Download Full-text

Method for Computational Estimation of Frost Resistance in Aircraft Paint Coatings

Herald of the Bauman Moscow State Technical University Series Mechanical Engineering ◽

10.18698/0236-3941-2020-3-4-17 ◽

2020 ◽

pp. 4-17

Author(s):

A.A. Aliyev ◽

A.Yu. Аmpilogov

Keyword(s):

Frost Resistance ◽

Linear Thermal Expansion ◽

Physical And Mechanical Properties ◽

Temperature Cycling ◽

Operating Conditions ◽

Computational Method ◽

Ice Accretion ◽

Freezing And Thawing ◽

Paint Coating ◽

Paint Coatings

The paper considers the issues of temperature cycling and ice accretion on external paint coatings of aircraft as well as the negative effects of these processes expressed in periodic tension-compression strain and absorption of atmospheric moisture by surface microasperities with its subsequent freezing resulting in gradual cavity wedging. We note that laboratory testing methods recreating the temperature cycling that simulates actual operating conditions of aircraft paint coatings are increasingly labour-intensive. We substantiate the feasibility of developing a computational method for frost resistance estimation in specific operating conditions. The method takes into account the combination of contraction stresses, excessive cooling and wedging caused by ice build-up. We assume the main physical and mechanical properties of ice and paint to be homogeneous and equal to cumulative average values, and the linear thermal expansion coefficients of the substrate and coating to be constant and not dependent on temperature. We disregard ice friction over the microasperity cavities and in-flight loads on the paint coating caused by incident air flows and structural deformations of the aircraft. We present a method of computing frost resistance of aircraft paint coating subjected to cyclical ice accretion, which is based on the method of equivalent stresses. We tested frost resistance of a polyesterurethane coating over a duralumin plate in the range of --50 to 25 °C for F = 2000 freezing and thawing cycles. We performed a temperature cycling computation of the factor of safety for frost resistance in the case of periodic ice accretion. The results obtained are in good agreement with experimental data

Download Full-text

Influence of Heat Treatment on the Corrosion Behaviour of Aluminium Silver Nano Particle/Calcium Carbonate Composite

Journal of Composites Science ◽

10.3390/jcs5100280 ◽

2021 ◽

Vol 5 (10) ◽

pp. 280

Author(s):

Omolayo Michael Ikumapayi ◽

Esther T. Akinlabi ◽

Olayinka Oluwatosin Abegunde ◽

Precious Ken-Ezihuo ◽

Henry A. Benjamin ◽

...

Keyword(s):

Heat Treatment ◽

Corrosion Rate ◽

Corrosion Behaviour ◽

Stir Casting ◽

Corrosion Properties ◽

Corrosive Media ◽

Loss Analysis ◽

Weight Composition ◽

Analysis Technique ◽

Hybrid Reinforcement

Corrosion is one of the leading sources of material failure and deterioration in society. Scholars have proposed different techniques to mitigate corrosion. This research study explores and validates one of these techniques. An Aluminium metal matrix (AMC) was produced using the stir casting method with various weight percentages of AgNp and CaCO3 reinforcements. Heat treatment was performed on the samples to enhance the metallurgical and corrosion properties of the materials. The corrosion rate of the AMC samples was tested in different corrosive media (neutral and acidic) with different concentrations using the weight loss analysis technique for several days. It was observed that the corrosion rate of the AMC relies on the nature of the electrolyte and the percentage concentration of this electrolyte. The heat treatment improves the corrosion resistance of the AMC samples. In addition, an increase in the % weight composition of the reinforcement (AgNp + CaCO3) results in a reduction in the corrosion rate of the AMC in both corrosive media. The optimal %weight composition was found to be 4% for the hybrid reinforcement of AgNp + CaCO3 and 6% for the CaCO3 reinforcement in both the untreated and heat-treated samples.

Download Full-text

MECHANICAL PROPERTIES OF THERMAL ARC SPRAY ALUMINIUM COATING IN ATMOSPHERIC CONDITION

Jurnal Teknologi ◽

10.11113/jt.v76.5795 ◽

2015 ◽

Vol 76 (10) ◽

Author(s):

Muhamad Hafiz Abd Malek ◽

Nor Hayati Saad ◽

Sunhaji Kiyai Abas ◽

Noriyati Mohd Shah

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Corrosion Rate ◽

Coating Thickness ◽

Salt Spray ◽

Atmospheric Condition ◽

Spray Coating ◽

Image Analyzer ◽

Arc Spray ◽

Two Samples

Thermal arc spray coating was regard as most preferred method as a protective coating due to its ability to sustain in high temperature, high friction surface, and low cost process. It has been applied by most of industrialist especially in oil and gas field, where current application of the coating used in onshore. This research is a study on mechanical properties of thermal arc spray coating by using aluminium alloy with purity 99.5% as coating material. Two samples with different coating thickness at range of 200 μm – 300 μm and 300 μm – 400 μm were used for this research. Some of tests were prepared to evaluate coating mechanical properties. Surface microstructures were viewed and analysed using scanning electron microscope and energy dispersive x-ray analysis. The hardness was inspected using Vickers Hardness testing. Corrosion rate was established by performing Salt Spray Test. Porosity value was calculated using Image Analyzer. Surface roughness was viewed using Infinitefocus G4 machine. Experimental results were found that coating porosity was raising with enhancing of coating thickness. The increment coating thickness also resulted in reduction of hardness and surface roughness. For corrosion rate purpose, two samples with coating thickness at range of 200 μm – 300 μm and two samples with coating thickness at range 300 μm – 400 μm were prepared. It recorded at Rating 5 – Rating 7 after exposed in salt spray cabinet within 144 hours. As a result, coating thickness at range of 200 μm – 300 μm performs the most efficiency in terms of mechanical properties; less corrosion rate, less porosity and contribute to high hardness and surface roughness.

Download Full-text