Mansour Farzam - Academia.edu (original) (raw)

Papers by Mansour Farzam

Journal of Coatings Technology and Research

In this research, the corrosion resistance and adhesion property of a synthetic rubber-based prim... more In this research, the corrosion resistance and adhesion property of a synthetic rubber-based primer reinforced with different ratios of micaceous iron oxide (MIO) pigments were studied. Coatings were applied on carbon steel panels and also on steel pipes of 219.1 mm outer diameter. Scanning electron microscopy (SEM) was used to investigate the dispersion of MIO particles in the rubbery matrix. The anticorrosion performance of the coatings was studied, using electrochemical impedance spectroscopy (EIS) and salt spray tests. In addition, the adhesion of primers to carbon steel substrates was evaluated by pull-off test. In order to investigate the effect of MIO particles on the flexibility of the pigmented primers, a cupping test was conducted. The adhesion of cold-applied tape to the formulated primers was assessed by peel adhesion test using hanging mass method. The results indicated that adding 5, 10, and 15 wt% of MIO pigments into the primer improved corrosion resistance of the coatings. An increase in the MIO loading up to 10 wt%, improved the adhesion of the primer to both steel substrate and cold-applied tape.

Progress in Color, Colorants and Coatings, Dec 20, 2013

Salt fog SEM ater based inorganic alkali silicate binder of zinc rich primer was modified by addi... more Salt fog SEM ater based inorganic alkali silicate binder of zinc rich primer was modified by adding acrylic resin derivatives. Several series of primer coatings were formulated by adding 5, 10 and 15 wt% of acrylic and acrylic/styrene copolymer to potassium silicate binder and used as binder in zinc rich coatings. The formulated primers were applied on low carbon steel plates and the corrosion protection properties of these primers were evaluated by electrochemical impedance spectroscopy (EIS), corrosion potential measurements, salt fog test and scanning electron microscope (SEM). The results indicated that the addition of 5% acrylic/styrene copolymer and/or 10% acrylic resin into the inorganic silicate binder led to improvement of corrosion protection performance of formulated primers.

Archives of Metallurgy and Materials, 2020

© 2020. The Author(s). This is an open-access article distributed under the terms of the Creative... more © 2020. The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial License (CC BY-NC 4.0, https://creativecommons.org/licenses/by-nc/4.0/deed.en which permits the use, redistribution of the material in any medium or format, transforming and building upon the material, provided that the article is properly cited, the use is noncommercial, and no modifications or adaptations are made. Arch. Metall. Mater. 65 (2020), 2, 627-638

The effect of heat input of submerged arc welding process on the corrosion bahavior of weld metal... more The effect of heat input of submerged arc welding process on the corrosion bahavior of weld metal of API X42 gas pipeline steel weld joint was investigated. For this purpose, 6 annealed sheets of 15mm thickness were prepared from the X42 microalloyed steel. Submerged arc welding process with varying heat input of 37.8, 18.9 and 12.6 kJ/mm was used for joint welding. Then potentiodynamic polarization and electrochemical impedance spectroscopy methods were used to evaluate the corrosion behavior of the welded joints (in 3.5% NaCl solution). The evaluation of the microstructures of the welded metals in the weld joints were conducted using the scanning electron microscopy. X-ray diffraction was used for the analysis of the phases formed in the weld metal microstructure. Scanning electron microscopy observations and patterns obtained from the X-ray diffraction showed that the increase in heat input resulted in the increase in the amount of ferrite. The grain size also increased. Corrosio...

Iranian Journal of Oil and Gas Science and Technology, 2014

The influence of increasing the SiO2/K2O molar ratio on the electrochemical action of a waterborn... more The influence of increasing the SiO2/K2O molar ratio on the electrochemical action of a waterborne potassium silicate zinc-rich coating was investigated by means of electrochemical impedance spectroscopy (EIS) and corrosion potential (Ecorr) measurements. The EIS results showed that increasing the SiO2/K2O molar ratio in the range of 3.135 to 5 by the addition of nano-SiO2 to the resins improved the resistance of coatings; however, higher molar ratios showed an adverse effect. Moreover, the alkali silicate binder of the sample with a SiO2/K2O molar ratio of 5 was improved by adding 5, 10, and 15 wt.% of acrylic resin and acrylic/styrene copolymer to potassium silicate resin. These formulated coatings were sprayed over carbon steel plates and the adhesion and morphology of these primers were evaluated by pull-off, cross cut, and scanning electron microscopy tests. Electrochemical measurements showed that the sample with a SiO2/K2O molar ratio of 5 had better corrosion properties than...

Tribology International, 2018

Nano-composite coatings with nano particles contents from 1 to 7 gr/lit, with the electroless bat... more Nano-composite coatings with nano particles contents from 1 to 7 gr/lit, with the electroless bath pHs of 4.5, 7, 9; and electroless bath rotating speeds of 200, 400 and 600 rpm were produced. Microstructural/elemental analyses were performed by various techniques. Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques were used to study corrosion behavior. Wear resistance of the coatings was assessed by ball on disk wear test. Results showed that wear resistance of the coatings was improved at higher concentration of particles and by increasing the pH of the electroless bath as well. These conditions reduced corrosion resistance of the coatings, increased phases such as Cu 2 P 7 , CuP 2 , and reduced the P content in the Cu nano-composite coatings.

Information regarding type, size, shape and location of the defects in objects can be obtained ea... more Information regarding type, size, shape and location of the defects in objects can be obtained easily by the new generation of ultrasonic instruments which use Phased Array technology. This investigation studies the results of ultrasonic test with Phased Array technology done on a storage vessel and matches them with environmental conditions like corrosion to detect the type of the defects with 100% certainty. Inspections show that the detected cracks in the shell metal are originally formed by hydrogen induced cracking and calculations show that these cracks will not grow up if the hydrogen diffusion through the metal is stopped. Therefore, it is predicted that the operation of the pressure vessel in normal condition and under regular supervision can be continued if a suitable coating is applied to the interior of the vessel to prevent hydrogen diffusion.

Journal of Thermal Analysis and Calorimetry, 2010

Iranian Journal of Oil and Gas Science and Technology, 2017

The effect of repeated repair welding, shielded with argon, on microstructural properties, corros... more The effect of repeated repair welding, shielded with argon, on microstructural properties, corrosion resistance, and dry sliding wear behavior of aluminum alloy 5083/H116 were investigated. Samples were welded by metal inert gas welding method. 100% argon was used to protect fusion zone. Aluminum alloy 5356 was used as the filler metal. The samples for microstructure, corrosion, and wear tests were prepared from welded and repaired plates. To study the microstructural properties, the samples were mounted, polished, and then etched by the Keller's solution. Optical microscopy was used for metallurgical analysis. The corrosion behavior was evaluated in 3.5% NaCl solution and at a temperature of 25 °C using a potentiodynamic polarization and electrochemical impedance spectroscopy methods. Dry sliding wear behavior was evaluated by pin on disc method and scanning electron microscopy.

In this research an extensive literature search into the mechanism of cavitation dynamics and its... more In this research an extensive literature search into the mechanism of cavitation dynamics and its consequences was conducted. A cavitation venturie rig was designed and constructed, and the cavitation number was checked mathematically. A new camera technique was developed to capture the cavitation cloud. Carbon steel (AISI 1020), stainless steel (AISI 304 and 316), ferritic alloy steel (B1274), brass (C27000), phosphor bronze (C51000) and aluminum bronze (C60800) test pieces were prepared and tested in the venturie tube. Aluminum bronze was the most and carbon steel the least resistant of these alloys, the measured mechanical properties could not systematically be correlated with cavitation resistance. The microscopic examinations showed that cavitation induced plastic deformation had caused the misalignment of polishing lines. A field study into the susceptibility of an Iranian sugar cane company's centrifugal pumps showed that deviation from the manuals hydraulic settings caus...

Anti-Corrosion Methods and Materials

Purpose Potassium silicate sealer was applied on solvent-cleaned, acid-pickled, dacromet-coated s... more Purpose Potassium silicate sealer was applied on solvent-cleaned, acid-pickled, dacromet-coated steel to improve its corrosion resistance. The purpose of this paper is to study the corrosion behavior of dacromet-coated steel. Design/methodology/approach Potassium silicate sealer was applied on solvent-cleaned, acid-pickled, dacromet-coated steel to improve its corrosion resistance. Electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and salt spray were carried out. SEM was used to study the morphological appearance of the surface. Findings The EIS behavior indicated that solvent-cleaned dacromet-coated steel sealed with potassium silicate showed that the corrosion current density was 2.664E − 5 A.cm2 which was reduced to 8.752E − 6 A.cm2 and the corrosion rate, which was 2.264E − 2 mm.year−1, was reduced to 7.438E − 3 mm.year−1 in NaCl 3.5 wt.per cent. EIS was used in NaCl 3.5 wt.%...

Materials Research Express

Canadian Metallurgical Quarterly

Materials Research

NiP -(Cu) composite coatings were applied on a St37 steel in an acidic bath of hypophosphite comp... more NiP -(Cu) composite coatings were applied on a St37 steel in an acidic bath of hypophosphite composite. The effect of the concentration of the Cu particles and pH of the solutionon the amount of Ni and P of the coatings, their morphology, and hardness of the coatings were explored. Some of the coated samples were also heat treated at 400ºC for 1 hour. The phases formed, the microstructure and the amount of the alloying elements of the coatings were analyzed by X-Ray powder diffraction (XRD), Scanning Electron Microscope (SEM) equiped with Energy Dispersive Spectroscopy (EDS). Results show that although adding Cu particles reduced the hardness of NiP coating (from 482.4 to 351.2 VH in 1 gr/lit Cu), within NiP -Cu composite coatings the hardness of NiP -Cu composite coating increased from 351.2 to 380.7 VH by increasing the Cu particles from 1 to 7 gr/lit. The structure of the coating was crystalline during the heat treatment making the coating harder. With increasing the pH of the solution from 4.5 to 7 and then to 9, the weight percent of P and the particle of Cu were reduced.

Materials and Design, Aug 27, 2013

ABSTRACT The purpose of this study is to evaluate changes in the mechanical, micro structural and... more ABSTRACT The purpose of this study is to evaluate changes in the mechanical, micro structural and the corrosion properties of stainless steel 316L under repeated repair welding. The welding and the repair welding were conducted by shielded metal arc welding (SMAW). The SMAW welding process was performed using E316L filler metals. Specimen of the base metal and different conditions of shielded metal arc welding repairs were studied by looking in the micro structural changes, the chemical composition of the phases, the grain size (in the heat affected zone) and the effect on the mechanical and corrosion properties. The microstructure was investigated using optical microscopy (OM) and scanning electron microscopy (SEM). The chemical composition of the phases was determined using energy dispersive spectrometry (EDS). The corrosion behavior in 1 M H2SO4 + 3.5% NaCl solution was evaluated using a potentiodynamic polarization method. Tensile tests, Charpy-V impact resistance and Brinell hardness tests were conducted. Hardness of the heat affected zone decreased as the number of repairs increased. Generally an increase in the yield strength (YS) and the ultimate tensile strength (UTS) occurred with welding. After the first repair, a gradual decrease in YS and UTS occurred but the values of YS and UTS were not less than values of the base metal. Significant reduction in Charpy-V impact resistance with the number of weld repairs were observed when the notch location was in the HAZ. The HAZ of welding repair specimen is more sensitive to pitting corrosion. The sensitivity of HAZ to pitting corrosion was increased by increasing the number of welding repair.

Permeation tests were conducted by Devanathan's electrochemical method and a newly invented elect... more Permeation tests were conducted by Devanathan's electrochemical method and a newly invented electro-vacuum method. Experiments illustrated that as the microstructure changed, the diffusion constant, D, changed. The steel BS 4360 when quenched, decreased its D value by 3.7 times that of the original plate. Comparing the behavior of AISI 4340 with API X52, it is noted that the D value of the latter alloy is 2.23 times that of API X52, due to the presence of less C and Ni content. Ingress of hydrogen increased with the reduction of voltage and pH. For alloy BS 4360, when the charging voltage was dropped by-400 mv, the D value increased by 62%. Thickness would not have a realistic effect, but cold work reduced D. The same alloy when cold worked by 72%, its D value decreased by 15%. The difference in D measured by the two methods of permeation was due to the variation in material, apparatus design and operation. Hydrogen degradation during stress corrosion and corrosion fatigue tests is one of the two processes of crack propogation. Immersion, dynamic polarization, stress corrosion (dynamic and static), corrosion fatigue tests, cathodic protection and fractographic studies were conducted in seawater and sour (hydrogen sulfide generated by sulfate reducing bacteria) environments. Overall, it was concluded that with regards to Nernest's equation, as the partial pressure of hydrogen increased, the value of D increased. Furthermore, the speed of hydrogen diffusion increased. In the sour environment, the overtaking mechanism of failure was found to be hydrogen embrittlement rather than anodic dissolution.

Corrosion is a naturally occurring phenomenon commonly defined as the deterioration of a substanc... more Corrosion is a naturally occurring phenomenon commonly defined as the deterioration of a substance (usually a metal) or its properties because of a reaction with its environment. According to the current U.S. corrosion study, the direct cost of metallic corrosion is $276 billion on an annual basis. This represents 3.1% of the U.S. Gross Domestic Product. Facilities due to corrosive environment of water suffer corrosion. Corrosion management is that part of the overall management system, which is concerned with the development, implementation, review and maintenance of the corrosion policy. The corrosion policy provides a structured framework for identification of risks associated with corrosion, and the development and operation of suitable risk control measures. A general corrosion management system has been outlined that provides a progressive framework that is compatible with the requirements of an offshore safety management system concerned with ensuring the integrity of topside...

Risk assessment is the quantitative analysis intended to predict the magnitude of the response as... more Risk assessment is the quantitative analysis intended to predict the magnitude of the response as the result of an event. In this case, the event is the presentation of a nanomaterial at a given rate or concentration, and the response is a physiological impairment within a defined receptor. The uniqueness of nanomaterials is based on the fact that they present an environmentally or toxicologically reactive entity with a multi atomic or multi molecular surface associated with non-surface constituent. The surface properties of these particles often differ from their molecular form with regard to photochemistry and electrochemistry as well as reactive thermodynamics. This paper concentrates firstly on aspects of the assessment process that would be specific and unique to nanomaterials, and secondly on how to integrate these considerations within a risk paradigm useful for the evaluation of human and ecological safety. It was found that, nanomaterials are less likely to induce systemic ...

Ni-matrix nanocomposite coatings with various contents of TiO2 nanoparticles were prepared by ele... more Ni-matrix nanocomposite coatings with various contents of TiO2 nanoparticles were prepared by electrodeposition in a Ni plating bath containing TiO2 nanoparticles to be codeposited. The wear behavior of the pure Ni and Ni-TiO2 nanocomposite coatings were evaluated by a pin-on-disc tribometer. The worn surface of coating was observed using a scanning electron microscope (SEM). It was found that the microhardness and wear resistance of the nanocomposite coatings increase with increasing of TiO2 nanoparticles content in the coating. The worn surface morphologies show that the Ni-TiO2 nanocomposite coatings exhibit less abrasive width and depth and less tendency for plastic deformation.