Dépouillements

Erosion–corrosion characteristic of nano-particulates reinforced Ni–Cr–Mo–Cu surface alloying layer in acidic flow and acidic slurry flow / J. Xu in Materials and corrosion, Vol. 61 N° 1 (Janvier 2010) 

Public ISBD [article]  in Materials and corrosion > Vol. 61 N° 1 (Janvier 2010) . - pp. 7–15 Titre : Erosion–corrosion characteristic of nano-particulates reinforced Ni–Cr–Mo–Cu surface alloying layer in acidic flow and acidic slurry flow Type de document : texte imprimé Auteurs : J. Xu, Auteur ; C. Zhuo, Auteur Année de publication : 2010 Article en page(s) : pp. 7–15 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : Composite  alloying  layer;  EIS;  erosion–corrosion  behavior;  nano-particle  reinforced;  potentiodynamic  polarization Résumé : In order to improve the corrosion and erosion–corrosion resistance of 316L stainless steel in engineering application, two kinds of composite alloying layers were prepared by a duplex treatment, consisting of Ni/nano-SiC and Ni/nano-SiO2 predeposited by brush plating, respectively, and a subsequent surface alloying with Ni–Cr–Mo–Cu by double glow process. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) were performed on the two kinds of composite alloying layer using 10 wt% HCl solution to assess the corrosion behavior. Erosion–corrosion tests were carried out by erosion–corrosion test rig in acidic flow and acidic slurry flow for test time of 20 h at four different rotational speeds. Results of electrochemical tests indicated that the corrosion resistance of composite alloying layer with brush plating Ni/nano-SiO2 particles interlayer approximated to that of single Ni-based alloying layer, whereas the corrosion resistance of the composite alloying layer with brush plating Ni/nano-SiC particles interlayer was apparently inferior to that of Ni-based alloying layer in 10 wt% HCl solution at static state. Under the conditions of acidic flow and acidic slurry flow, the mass losses of tested samples increased with increase in the time of erosion–corrosion tests and the rotational speeds of samples. The mass losses of composite alloying layer with brush plating Ni/nano-SiO2 particles interlayer were lower than that of single Ni-based alloying layer at all rotational speeds, except at 1.88 m/s in acidic flow. The mass losses of composite alloying layer with brush plating Ni/nano-SiC particles interlayer were higher than that of single Ni-based alloying layer at all rotational speeds, but were obviously lower than that of AISI 316L stainless steel. The influences of second phase on the corrosion and erosion–corrosion of the two kinds of composite alloying layer were discussed in this paper. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905235/abstract [article] Erosion–corrosion characteristic of nano-particulates reinforced Ni–Cr–Mo–Cu surface alloying layer in acidic flow and acidic slurry flow [texte imprimé] / J. Xu, Auteur ; C. Zhuo, Auteur . - 2010 . - pp. 7–15. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 61 N° 1 (Janvier 2010) . - pp. 7–15 Mots-clés : Composite  alloying  layer;  EIS;  erosion–corrosion  behavior;  nano-particle  reinforced;  potentiodynamic  polarization Résumé : In order to improve the corrosion and erosion–corrosion resistance of 316L stainless steel in engineering application, two kinds of composite alloying layers were prepared by a duplex treatment, consisting of Ni/nano-SiC and Ni/nano-SiO2 predeposited by brush plating, respectively, and a subsequent surface alloying with Ni–Cr–Mo–Cu by double glow process. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) were performed on the two kinds of composite alloying layer using 10 wt% HCl solution to assess the corrosion behavior. Erosion–corrosion tests were carried out by erosion–corrosion test rig in acidic flow and acidic slurry flow for test time of 20 h at four different rotational speeds. Results of electrochemical tests indicated that the corrosion resistance of composite alloying layer with brush plating Ni/nano-SiO2 particles interlayer approximated to that of single Ni-based alloying layer, whereas the corrosion resistance of the composite alloying layer with brush plating Ni/nano-SiC particles interlayer was apparently inferior to that of Ni-based alloying layer in 10 wt% HCl solution at static state. Under the conditions of acidic flow and acidic slurry flow, the mass losses of tested samples increased with increase in the time of erosion–corrosion tests and the rotational speeds of samples. The mass losses of composite alloying layer with brush plating Ni/nano-SiO2 particles interlayer were lower than that of single Ni-based alloying layer at all rotational speeds, except at 1.88 m/s in acidic flow. The mass losses of composite alloying layer with brush plating Ni/nano-SiC particles interlayer were higher than that of single Ni-based alloying layer at all rotational speeds, but were obviously lower than that of AISI 316L stainless steel. The influences of second phase on the corrosion and erosion–corrosion of the two kinds of composite alloying layer were discussed in this paper. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905235/abstract

Inhibition of copper corrosion by modifying cysteine self-assembled film with alkylamine/alkylacid compounds / D.-Q. Zhang in Materials and corrosion, Vol. 61 N° 1 (Janvier 2010) 

Public ISBD [article]  in Materials and corrosion > Vol. 61 N° 1 (Janvier 2010) . - pp. 16–21 Titre : Inhibition of copper corrosion by modifying cysteine self-assembled film with alkylamine/alkylacid compounds Type de document : texte imprimé Auteurs : D.-Q. Zhang, Auteur ; L.-X. Gao, Auteur ; Q.-R. Cai, Auteur Année de publication : 2010 Article en page(s) : pp. 16–21 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : Amino  acid;  copper;  corrosion;  modification;  self-assembled  monolayers  (SAMs) Résumé : Complex self-assembled monolayers (SAMs) were prepared by modifying the adsorption of cysteine with dodecylacid (DAC) and with dodecylamine (DAM) on copper surfaces. Their protective effects against copper corrosion were investigated by potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS) in 0.5 M HCl aqueous solution. Results show that SAMs suppress cathodic current densities and shift the corrosion potential toward more negative values. Two types of complex SAMs enhance the anticorrosion effect of cysteine SAMs. PM3 semi-empirical quantum calculations were used to obtain the quantum chemical parameters. The complex SAMs formed from cysteine and DAM have the higher EHOMO level and the better protection effect. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905225/abstract [article] Inhibition of copper corrosion by modifying cysteine self-assembled film with alkylamine/alkylacid compounds [texte imprimé] / D.-Q. Zhang, Auteur ; L.-X. Gao, Auteur ; Q.-R. Cai, Auteur . - 2010 . - pp. 16–21. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 61 N° 1 (Janvier 2010) . - pp. 16–21 Mots-clés : Amino  acid;  copper;  corrosion;  modification;  self-assembled  monolayers  (SAMs) Résumé : Complex self-assembled monolayers (SAMs) were prepared by modifying the adsorption of cysteine with dodecylacid (DAC) and with dodecylamine (DAM) on copper surfaces. Their protective effects against copper corrosion were investigated by potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS) in 0.5 M HCl aqueous solution. Results show that SAMs suppress cathodic current densities and shift the corrosion potential toward more negative values. Two types of complex SAMs enhance the anticorrosion effect of cysteine SAMs. PM3 semi-empirical quantum calculations were used to obtain the quantum chemical parameters. The complex SAMs formed from cysteine and DAM have the higher EHOMO level and the better protection effect. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905225/abstract

Performance of Cu and Cu-Zn alloy in the Arabian Gulf environment / H. Saricimen in Materials and corrosion, Vol. 61 N° 1 (Janvier 2010) 

Public ISBD [article]  in Materials and corrosion > Vol. 61 N° 1 (Janvier 2010) . - pp. 22-29 Titre : Performance of Cu and Cu-Zn alloy in the Arabian Gulf environment Type de document : texte imprimé Auteurs : H. Saricimen, Auteur ; A. Quddus, Auteur ; A. Ahmad, Auteur Année de publication : 2010 Article en page(s) : pp. 22-29 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : Atmosphere;  brass;  chloride;  copper;  corrosion;  corrosion  rate;  splash  zone;  sulfate;  underground;  weight  loss Résumé : Corrosion performance of copper and brass coupons during 15 month exposure in atmosphere, underground and splash zone conditions was undertaken at Khaleej Mardumah test site located in the industrial/coastal city of Jubail along the Arabian Gulf coast, Saudi Arabia. The environmental indicators such as soil, groundwater, seawater, and air particulate samples were assessed. The exposed corrosion coupons were examined by scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and X-ray fluorescence (XRF) to identify the corrosion products and study their surface morphology. Corrosion rate was determined by weight loss method. The experimental results indicated that a high degree of variation in temperature and humidity in this region combined with high chloride and sulfate concentrations was primarily responsible for the corrosion of copper and brass at Khaleej Mardumah test site. Underground environment was the most corrosive to both copper and brass coupons studied, followed by splash zone. Corrosion rates were found to range from 4.29 to 10.84 µm/y for copper and from 2.47 to 29.31 µm/y for brass. Corrosion rates of copper and brass obtained in this study are also compared with those reported for other locations worldwide. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905240/abstract [article] Performance of Cu and Cu-Zn alloy in the Arabian Gulf environment [texte imprimé] / H. Saricimen, Auteur ; A. Quddus, Auteur ; A. Ahmad, Auteur . - 2010 . - pp. 22-29. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 61 N° 1 (Janvier 2010) . - pp. 22-29 Mots-clés : Atmosphere;  brass;  chloride;  copper;  corrosion;  corrosion  rate;  splash  zone;  sulfate;  underground;  weight  loss Résumé : Corrosion performance of copper and brass coupons during 15 month exposure in atmosphere, underground and splash zone conditions was undertaken at Khaleej Mardumah test site located in the industrial/coastal city of Jubail along the Arabian Gulf coast, Saudi Arabia. The environmental indicators such as soil, groundwater, seawater, and air particulate samples were assessed. The exposed corrosion coupons were examined by scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and X-ray fluorescence (XRF) to identify the corrosion products and study their surface morphology. Corrosion rate was determined by weight loss method. The experimental results indicated that a high degree of variation in temperature and humidity in this region combined with high chloride and sulfate concentrations was primarily responsible for the corrosion of copper and brass at Khaleej Mardumah test site. Underground environment was the most corrosive to both copper and brass coupons studied, followed by splash zone. Corrosion rates were found to range from 4.29 to 10.84 µm/y for copper and from 2.47 to 29.31 µm/y for brass. Corrosion rates of copper and brass obtained in this study are also compared with those reported for other locations worldwide. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905240/abstract

Effect of Ag addition on the corrosion properties of Sn-based solder alloys / Q. V. Bui in Materials and corrosion, Vol. 61 N° 1 (Janvier 2010) 

Public ISBD [article]  in Materials and corrosion > Vol. 61 N° 1 (Janvier 2010) . - pp. 30-33 Titre : Effect of Ag addition on the corrosion properties of Sn-based solder alloys Type de document : texte imprimé Auteurs : Q. V. Bui, Auteur ; N. D. Nam, Auteur ; B.-I. Noh, Auteur Année de publication : 2010 Article en page(s) : pp. 30-33 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : Alloy;  corrosion;  intermetallic  compounds;  lead  free  solder;  microstructure Résumé : Corrosion properties of three different Sn-Ag lead free solder alloys have been investigated in 0.3 wt% Na2SO4 solution as corrosive environment. As cast solder alloy was analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Volume fractions of the Ag3Sn in the solders were determined by image analysis technique. Pitting potential and corrosion potential for the alloys were determined by potentiodynamic tests. Electrochemical impedance spectroscopy (EIS) was carried out to measure the film and charge transfer resistance. Alloys with lower Ag content have been found as better corrosion resistance material. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905237/abstract [article] Effect of Ag addition on the corrosion properties of Sn-based solder alloys [texte imprimé] / Q. V. Bui, Auteur ; N. D. Nam, Auteur ; B.-I. Noh, Auteur . - 2010 . - pp. 30-33. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 61 N° 1 (Janvier 2010) . - pp. 30-33 Mots-clés : Alloy;  corrosion;  intermetallic  compounds;  lead  free  solder;  microstructure Résumé : Corrosion properties of three different Sn-Ag lead free solder alloys have been investigated in 0.3 wt% Na2SO4 solution as corrosive environment. As cast solder alloy was analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Volume fractions of the Ag3Sn in the solders were determined by image analysis technique. Pitting potential and corrosion potential for the alloys were determined by potentiodynamic tests. Electrochemical impedance spectroscopy (EIS) was carried out to measure the film and charge transfer resistance. Alloys with lower Ag content have been found as better corrosion resistance material. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905237/abstract

The effects of various formwork surfaces on the corrosion performance of reinforcing steel in concrete / S. Subasi in Materials and corrosion, Vol. 61 N° 1 (Janvier 2010) 

Public ISBD [article]  in Materials and corrosion > Vol. 61 N° 1 (Janvier 2010) . - pp. 34–42 Titre : The effects of various formwork surfaces on the corrosion performance of reinforcing steel in concrete Type de document : texte imprimé Auteurs : S. Subasi, Auteur ; M. Arslan, Auteur ; G. Durmus, Auteur Année de publication : 2010 Article en page(s) : pp. 34–42 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : Chloride;  concrete;  corrosion;  formwork  surface;  reinforcing  bar Résumé : In this study, the effects of various formwork surfaces on the corrosion performance of reinforcing steel in concrete were examined. For this purpose, seven formwork surfaces from populus nigra, pinus silvestris, steel sheet, and four of plywoods were prepared. Three of the plywood formworks were covered with different geotextile liners and drainage channel and holes were drilled on their surfaces. One of the plywood formworks having no processes on its surface was for control. Reinforcing steels were first embedded in formworks and then the concrete was poured. The samples were exposed to corrosion in a way of settling them in 5% NaCl solution. We tested the corrosion potential and bonding strength of the samples. Later, the mass loss and tensile strength were measured on reinforcing bars that were pulled out from the concrete. The chloride content and pH values were also tested on concrete powders. The results indicated that drained-lined formwork (F5 with TB50 + F613 geotextile liner) compared to steel sheet (F4 undrained and unlined) gave 16% lower corrosion and 68% higher bonding strength on reinforcing bars embedded samples, 73% lower mass loss and 4% higher tensile strength on reinforcing bars, and 70% lower chloride content and 4% higher pH on concrete powders. In addition, it was found that the corrosion strength of reinforcing steels in concrete could be increased if drained-lined formworks were utilized. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905236/abstract [article] The effects of various formwork surfaces on the corrosion performance of reinforcing steel in concrete [texte imprimé] / S. Subasi, Auteur ; M. Arslan, Auteur ; G. Durmus, Auteur . - 2010 . - pp. 34–42. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 61 N° 1 (Janvier 2010) . - pp. 34–42 Mots-clés : Chloride;  concrete;  corrosion;  formwork  surface;  reinforcing  bar Résumé : In this study, the effects of various formwork surfaces on the corrosion performance of reinforcing steel in concrete were examined. For this purpose, seven formwork surfaces from populus nigra, pinus silvestris, steel sheet, and four of plywoods were prepared. Three of the plywood formworks were covered with different geotextile liners and drainage channel and holes were drilled on their surfaces. One of the plywood formworks having no processes on its surface was for control. Reinforcing steels were first embedded in formworks and then the concrete was poured. The samples were exposed to corrosion in a way of settling them in 5% NaCl solution. We tested the corrosion potential and bonding strength of the samples. Later, the mass loss and tensile strength were measured on reinforcing bars that were pulled out from the concrete. The chloride content and pH values were also tested on concrete powders. The results indicated that drained-lined formwork (F5 with TB50 + F613 geotextile liner) compared to steel sheet (F4 undrained and unlined) gave 16% lower corrosion and 68% higher bonding strength on reinforcing bars embedded samples, 73% lower mass loss and 4% higher tensile strength on reinforcing bars, and 70% lower chloride content and 4% higher pH on concrete powders. In addition, it was found that the corrosion strength of reinforcing steels in concrete could be increased if drained-lined formworks were utilized. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905236/abstract

Susceptibility to corrosion damage of pipeline steels under coating disbondments / N. Guermazi in Materials and corrosion, Vol. 61 N° 1 (Janvier 2010) 

Public ISBD [article]  in Materials and corrosion > Vol. 61 N° 1 (Janvier 2010) . - pp. 43–50 Titre : Susceptibility to corrosion damage of pipeline steels under coating disbondments Type de document : texte imprimé Auteurs : N. Guermazi, Auteur ; A. Ibrahmi, Auteur ; H. Hmidi, Auteur Année de publication : 2010 Article en page(s) : pp. 43–50 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : Electrochemical  tests;  gravimetric  measurements;  pipeline  corrosion Résumé : This study provides an experimental investigation on the corrosion behaviour of three carbon steels used for pipeline application. The susceptibility of these materials to corrosion damage was analysed in order to simulate its service conditions particularly under disbonded coating. Monitoring of open-circuit potential (Efree), polarization resistance (Rp) and measuring of the weight loss during immersion time were used to evaluate the corrosion behaviour of the studied materials. All the corrosion experiments were performed in two aqueous solutions: natural seawater and synthetic one (3 wt% NaCl solution). The morphology of the corrosion products was examined by optical microscopy. The results obtained from electrochemical tests have shown different behaviour for the studied steels into the retained corrosive environments: more stable potentials (Efree), higher Rp-values with large fluctuations evolution were found in natural seawater. The gravimetric measurements have also shown a continuous variation of the weight loss throughout the exposure period in the sodium chloride solution. However, it seemed that a passive behaviour was observed in natural seawater. A little difference was observed between all the studied steels in terms of corrosion kinetics. The steel, having the little ferritic grain size, seems to be more resistant to corrosion damage. Qualitatively, a porous and non-adherent oxide film was observed on the corroded surface in the synthetic solution; while, the rust layer, which is formed in the natural seawater, has acted as a barrier of corrosion process. Finally, all the results obtained from both electrochemical tests and weight loss measurements were in reasonably good accordance. The important common point that can be concluded was that all the tested materials seem to be more suitable for natural seawater than 3 wt% NaCl solution. Also, they are not recommendable to be used in an environment where chloride attack is possible and important. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905233/abstract [article] Susceptibility to corrosion damage of pipeline steels under coating disbondments [texte imprimé] / N. Guermazi, Auteur ; A. Ibrahmi, Auteur ; H. Hmidi, Auteur . - 2010 . - pp. 43–50. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 61 N° 1 (Janvier 2010) . - pp. 43–50 Mots-clés : Electrochemical  tests;  gravimetric  measurements;  pipeline  corrosion Résumé : This study provides an experimental investigation on the corrosion behaviour of three carbon steels used for pipeline application. The susceptibility of these materials to corrosion damage was analysed in order to simulate its service conditions particularly under disbonded coating. Monitoring of open-circuit potential (Efree), polarization resistance (Rp) and measuring of the weight loss during immersion time were used to evaluate the corrosion behaviour of the studied materials. All the corrosion experiments were performed in two aqueous solutions: natural seawater and synthetic one (3 wt% NaCl solution). The morphology of the corrosion products was examined by optical microscopy. The results obtained from electrochemical tests have shown different behaviour for the studied steels into the retained corrosive environments: more stable potentials (Efree), higher Rp-values with large fluctuations evolution were found in natural seawater. The gravimetric measurements have also shown a continuous variation of the weight loss throughout the exposure period in the sodium chloride solution. However, it seemed that a passive behaviour was observed in natural seawater. A little difference was observed between all the studied steels in terms of corrosion kinetics. The steel, having the little ferritic grain size, seems to be more resistant to corrosion damage. Qualitatively, a porous and non-adherent oxide film was observed on the corroded surface in the synthetic solution; while, the rust layer, which is formed in the natural seawater, has acted as a barrier of corrosion process. Finally, all the results obtained from both electrochemical tests and weight loss measurements were in reasonably good accordance. The important common point that can be concluded was that all the tested materials seem to be more suitable for natural seawater than 3 wt% NaCl solution. Also, they are not recommendable to be used in an environment where chloride attack is possible and important. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905233/abstract

The influence of tin and silver as microstructure modifiers on the corrosion rate of Pb–Ca alloys in sulfuric acid solutions / M. I. Cekerevac in Materials and corrosion, Vol. 61 N° 1 (Janvier 2010) 

Public ISBD [article]  in Materials and corrosion > Vol. 61 N° 1 (Janvier 2010) . - pp. 51–57 Titre : The influence of tin and silver as microstructure modifiers on the corrosion rate of Pb–Ca alloys in sulfuric acid solutions Type de document : texte imprimé Auteurs : M. I. Cekerevac, Auteur ; E. Romhanji, Auteur ; Z. Cvijovic, Auteur Année de publication : 2010 Article en page(s) : pp. 51–57 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : Corrosion  rate;  Lead–acid  batteries;  mechanical  treatment;  microstructure  of  alloys;  Pb–Ca–Sn–Ag  alloys;  potentiodynamic  polarization;  thermal  treatment Résumé : The effect of microstructure modifiers, Sn and Ag, on the corrosion rate of commercial Pb–Ca alloy in H2SO4 electrolyte was investigated by the potentiodynamic polarization and by the weight loss corrosion rate measurement at the open circuit potential. The effect of microstructure modification of the Pb–Ca alloy, provoked by the alloying with tin and silver as well as by the proper thermo-mechanical treatment, is recorded by optical microscopy. The weight loss experiments have shown three- to five-fold decreases in the corrosion rate of ternary Pb–Ca–Sn and quaternary Pb–Ca–Sn–Ag alloys, compared to the results for primary Pb–Ca alloy. It is largely in accordance with the results of potentiodynamic polarization measurements that showed comparable decrease in the passive current density of the modified alloys. The obtained results are discussed in terms of the synergetic effect of the addition of modifiers and the thermo-mechanical treatment on to the Pb–Ca alloy microstructure refinement, and accordingly the increase in their corrosion resistance. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905246/abstract [article] The influence of tin and silver as microstructure modifiers on the corrosion rate of Pb–Ca alloys in sulfuric acid solutions [texte imprimé] / M. I. Cekerevac, Auteur ; E. Romhanji, Auteur ; Z. Cvijovic, Auteur . - 2010 . - pp. 51–57. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 61 N° 1 (Janvier 2010) . - pp. 51–57 Mots-clés : Corrosion  rate;  Lead–acid  batteries;  mechanical  treatment;  microstructure  of  alloys;  Pb–Ca–Sn–Ag  alloys;  potentiodynamic  polarization;  thermal  treatment Résumé : The effect of microstructure modifiers, Sn and Ag, on the corrosion rate of commercial Pb–Ca alloy in H2SO4 electrolyte was investigated by the potentiodynamic polarization and by the weight loss corrosion rate measurement at the open circuit potential. The effect of microstructure modification of the Pb–Ca alloy, provoked by the alloying with tin and silver as well as by the proper thermo-mechanical treatment, is recorded by optical microscopy. The weight loss experiments have shown three- to five-fold decreases in the corrosion rate of ternary Pb–Ca–Sn and quaternary Pb–Ca–Sn–Ag alloys, compared to the results for primary Pb–Ca alloy. It is largely in accordance with the results of potentiodynamic polarization measurements that showed comparable decrease in the passive current density of the modified alloys. The obtained results are discussed in terms of the synergetic effect of the addition of modifiers and the thermo-mechanical treatment on to the Pb–Ca alloy microstructure refinement, and accordingly the increase in their corrosion resistance. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905246/abstract

Hot water acid-resistant enamels for sheet steel / A. S. Kassem in Materials and corrosion, Vol. 61 N° 1 (Janvier 2010) 

Public ISBD [article]  in Materials and corrosion > Vol. 61 N° 1 (Janvier 2010) . - pp. 58–63 Titre : Hot water acid-resistant enamels for sheet steel Type de document : texte imprimé Auteurs : A. S. Kassem, Auteur ; M. Z. Mostafa, Auteur ; M. F. Abadir, Auteur Année de publication : 2010 Article en page(s) : pp. 58–63 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : Sheet  steel;  enamel;  hot  water  tanks Résumé : Several enamel frit recipes were formulated for direct-on application on sheet steel. Their suitability as hot water and acid-resistant coatings were investigated. DTA analyses were performed on raw batches to follow up physico-chemical changes occurring on firing. Then batches with different recipe compositions were fritted and mixed with mill additions. These were then tested for thermal expansion and the corresponding linear coefficients as well as glass transition temperatures and softening points were obtained. Also, the viscosity of molten frits was determined as a function of temperature. These frits were then applied on sheet steel and the following properties were investigated: resistance to hot water, acid resistance, surface gloss, and adherence to steel. It was found that recipe No. 4, containing no manganese dioxide and the highest amount of nickel oxide among all the suggested recipes, gave the best results. The optimum conditions for application on steel sheet were: firing at 850 °C for 5 min. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200805230/abstract [article] Hot water acid-resistant enamels for sheet steel [texte imprimé] / A. S. Kassem, Auteur ; M. Z. Mostafa, Auteur ; M. F. Abadir, Auteur . - 2010 . - pp. 58–63. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 61 N° 1 (Janvier 2010) . - pp. 58–63 Mots-clés : Sheet  steel;  enamel;  hot  water  tanks Résumé : Several enamel frit recipes were formulated for direct-on application on sheet steel. Their suitability as hot water and acid-resistant coatings were investigated. DTA analyses were performed on raw batches to follow up physico-chemical changes occurring on firing. Then batches with different recipe compositions were fritted and mixed with mill additions. These were then tested for thermal expansion and the corresponding linear coefficients as well as glass transition temperatures and softening points were obtained. Also, the viscosity of molten frits was determined as a function of temperature. These frits were then applied on sheet steel and the following properties were investigated: resistance to hot water, acid resistance, surface gloss, and adherence to steel. It was found that recipe No. 4, containing no manganese dioxide and the highest amount of nickel oxide among all the suggested recipes, gave the best results. The optimum conditions for application on steel sheet were: firing at 850 °C for 5 min. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200805230/abstract

Exemplaires

Bibliothèque Ecole Nationale Polytechnique d'Alger

Accueil

Se connecter

Météo

Adresse