Documents disponibles écrits par cet auteur

A new theory for the negative difference effect in magnesium corrosion / S. Bender in Materials and corrosion, Vol. 63 N° 8 (Août 2012) 

Public ISBD [article]  in Materials and corrosion > Vol. 63 N° 8 (Août 2012) . - pp. 707–712 Titre : A new theory for the negative difference effect in magnesium corrosion Type de document : texte imprimé Auteurs : S. Bender, Auteur ; J. Goellner, Auteur ; A. Heyn, Auteur Année de publication : 2013 Article en page(s) : pp. 707–712 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : Current  density-potential-curve;  magnesium  alloys;  magnesium  corrosion;  negative  difference  effect;  polarization  measurements Résumé : An unusual feature known as the negative difference effect (NDE) can be observed in magnesium when recording corrosion current density–potential curves. More hydrogen is evolved at a more positive potential which does not occur in conventional metals. Several models have been proposed in the literature in order to explain the phenomenon of NDE. They succeed in explaining some effects, and fail to deal with others. A new model, which explains the NDE by two electron consuming processes, is presented in this paper. By potentiostatic investigations of magnesium in a chloride electrolyte, measurements of hydrogen evolution and chemical analysis of the electrolyte the new model was experimentally verified. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.201106225/abstract [article] A new theory for the negative difference effect in magnesium corrosion [texte imprimé] / S. Bender, Auteur ; J. Goellner, Auteur ; A. Heyn, Auteur . - 2013 . - pp. 707–712. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 63 N° 8 (Août 2012) . - pp. 707–712 Mots-clés : Current  density-potential-curve;  magnesium  alloys;  magnesium  corrosion;  negative  difference  effect;  polarization  measurements Résumé : An unusual feature known as the negative difference effect (NDE) can be observed in magnesium when recording corrosion current density–potential curves. More hydrogen is evolved at a more positive potential which does not occur in conventional metals. Several models have been proposed in the literature in order to explain the phenomenon of NDE. They succeed in explaining some effects, and fail to deal with others. A new model, which explains the NDE by two electron consuming processes, is presented in this paper. By potentiostatic investigations of magnesium in a chloride electrolyte, measurements of hydrogen evolution and chemical analysis of the electrolyte the new model was experimentally verified. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.201106225/abstract

Relevance of the cathodic process on the passivation of stainless steels / H. Sarmiento Klapper in Materials and corrosion, Vol. 63 N° 1 (Janvier 2012) 

Public ISBD [article]  in Materials and corrosion > Vol. 63 N° 1 (Janvier 2012) . - pp. 54–58 Titre : Relevance of the cathodic process on the passivation of stainless steels : An approximation to the origin of the rouging phenomenon Type de document : texte imprimé Auteurs : H. Sarmiento Klapper, Auteur ; J. Göllner, Auteur ; A. Heyn, Auteur Année de publication : 2012 Article en page(s) : pp. 54–58 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Cathodic  process  Electrochemical  noise  Rouging  Stainless  steel Résumé : Unwanted corrosive phenomena on stainless steel surfaces like rouging had been observed for years occurring at certain service conditions. Rouging consists in the formation of a colored surface film containing mainly iron on metallic surfaces in contact with high-purity waters. In spite of numerous hypotheses and experimental examinations a clear explanation about the origin of rouging on stainless steels is currently still lacking. Because rouging occurs even at well passivated stainless steel surfaces the origin of this corrosive phenomenon should be related to the weakness of the stability of the passive film. In the present paper electrochemical noise measurements regarding the stability of the passive layer of alloy 904L (1.4539, X1NiCrMoCu25-20-5) in high-purity water at 70 °C depending on the cathodic process are presented. In addition, the importance of the cathodic reaction on the passivation and stability of the passive layer is discussed. DEWEY : 620.1 ISSN : 0947-5117 En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.201005668/abstract [article] Relevance of the cathodic process on the passivation of stainless steels : An approximation to the origin of the rouging phenomenon [texte imprimé] / H. Sarmiento Klapper, Auteur ; J. Göllner, Auteur ; A. Heyn, Auteur . - 2012 . - pp. 54–58. Génie Mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 63 N° 1 (Janvier 2012) . - pp. 54–58 Mots-clés : Cathodic  process  Electrochemical  noise  Rouging  Stainless  steel Résumé : Unwanted corrosive phenomena on stainless steel surfaces like rouging had been observed for years occurring at certain service conditions. Rouging consists in the formation of a colored surface film containing mainly iron on metallic surfaces in contact with high-purity waters. In spite of numerous hypotheses and experimental examinations a clear explanation about the origin of rouging on stainless steels is currently still lacking. Because rouging occurs even at well passivated stainless steel surfaces the origin of this corrosive phenomenon should be related to the weakness of the stability of the passive film. In the present paper electrochemical noise measurements regarding the stability of the passive layer of alloy 904L (1.4539, X1NiCrMoCu25-20-5) in high-purity water at 70 °C depending on the cathodic process are presented. In addition, the importance of the cathodic reaction on the passivation and stability of the passive layer is discussed. DEWEY : 620.1 ISSN : 0947-5117 En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.201005668/abstract