Accueil
Détail de l'auteur
Auteur Subrahmanya Shreepathi |
Documents disponibles écrits par cet auteur
Ajouter le résultat dans votre panier Affiner la recherche
Investigating the role of key ingredients on cathodic delamination resistance of high-build pigmented epoxy coatings / R. Balaji in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 10, N° 1 (01/2013)
[article]
Titre : Investigating the role of key ingredients on cathodic delamination resistance of high-build pigmented epoxy coatings Type de document : texte imprimé Auteurs : R. Balaji, Auteur ; Kishor Gadhave, Auteur ; Subrahmanya Shreepathi, Auteur ; V. Akilan, Auteur ; B. P. Mallik, Auteur Année de publication : 2013 Article en page(s) : p. 87-95 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Bases (chimie)
Décollement cathodique (revêtement)
Epoxydes
Farinage (défauts)
Résistance à l'arrachement
Résistance chimique
RevêtementsIndex. décimale : 667.9 Revêtements et enduits Résumé : Organic coatings applied on cathodically protected metallic structures must have good resistance to cathodic delamination or disbonding (CD). Both environmental conditions and coating composition influence the CD resistance. In the present study, the effect of types of epoxy resin, curing agents and their mixing ratio on cathodic delamination rate was studied in a high-build pigmented coating. Furthermore, the influence of platey fillers on CD resistance was also studied. In order to bring out correlations, if any, between adhesion and CD resistance, pull-off adhesion strengths (both dry and wet) of these coatings were also measured. Fairly good correlation was found between residual (wet) pull-off adhesion strength and CD resistance. When tested at 60 and 90°C, all the coatings under investigation showed chalking. Among the coatings under investigation, the one based on Bisphenol F epoxy and modified cycloaliphatic amine adduct exhibited excellent CD resistance. Note de contenu : - EXPERIMENTAL : Materials and reagents - Processing of coatings - Coating application - CD testing - Characterization
- RESULTS AND DISCUSSION : Effect of curing agent on cathodic delamination - Effect of type of epoxy resin on cathodic disbonding - Effect of base-to-hardener ratio on CD resistance - Pull-off adhesion strength vs CD resistance - Chalking during CD testDOI : 10.1007/s11998-012-9460-4 En ligne : https://link.springer.com/content/pdf/10.1007%2Fs11998-012-9460-4.pdf Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=17476
in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 10, N° 1 (01/2013) . - p. 87-95[article]Réservation
Réserver ce document
Exemplaires (2)
Code-barres Cote Support Localisation Section Disponibilité 14636 - Périodique Bibliothèque principale Documentaires Disponible 15124 - Périodique Bibliothèque principale Documentaires Disponible Service life prediction of organic coatings: electrochemical impedance spectroscopy vs actual service life / Subrahmanya Shreepathi in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 8, N° 2 (03/2011)
[article]
Titre : Service life prediction of organic coatings: electrochemical impedance spectroscopy vs actual service life Type de document : texte imprimé Auteurs : Subrahmanya Shreepathi, Auteur ; Akshay Kumar Guin, Auteur ; Shrikant M. Naik, Auteur ; Mohan Rao Vattipalli, Auteur Année de publication : 2011 Article en page(s) : p. 191-200 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Durée de vie (Ingénierie)
Electrochimie
Essais accélérés (technologie)
Essais de brouillard salin
Spectroscopie d'impédance électrochimiqueIndex. décimale : 667.9 Revêtements et enduits Résumé : Electrochemical impedance spectroscopy (EIS) is used to derive an expression for predicting the service life of organic coating in a C4-type environment (industrial and costal areas with moderate salinity) as defined in ISO 12944 standard for paints and varnishes—corrosion protection of steel structures by protective paint systems. Three coating systems with a record of 2, 5, and 10 years of durability were selected for the study. The selection was also based on proven composition and dry film thickness (DFT) of the coatings as per ISO 12944. Electrochemical impedance measurements of the paint-coated panels were carried out by exposing the coated mild steel panels without scribe in different corrosive environments such as immersion in NaCl solution, neutral salt spray, etc. Neutral salt spray exposure was found to be the most severe corrosive environment among all the three coating systems. In most of the cases, EIS gave early indication of coating failure when compared to visual defects such as blistering and over-film corrosion. Note de contenu : - EXPERIMENTAL :
System 1 : Low durable system for normal inland
System 2 : Mdium durable system for coastal environment
- RESULTS AND DISCUSSION :
Exposure to immersion in 3.5 % NaCl
Exposure to ASTM B117 (neutral salt spray)
ASTM G85 (Prohesion cabinet test)
ASTM D5894 (cyclic corrosion test)
Immersionin 10 % HS2O4 and NaOH
Service life predictionDOI : 10.1007/s11998-010-9299-5 En ligne : https://link.springer.com/content/pdf/10.1007%2Fs11998-010-9299-5.pdf Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=11361
in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 8, N° 2 (03/2011) . - p. 191-200[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 012999 - Périodique Bibliothèque principale Documentaires Disponible Water transportation through organic coatings : correlation between electrochemical impedance measurements, gravimetry, and water vapor permeability / Subrahmanya Shreepathi in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 9, N° 4 (07/2012)
[article]
Titre : Water transportation through organic coatings : correlation between electrochemical impedance measurements, gravimetry, and water vapor permeability Type de document : texte imprimé Auteurs : Subrahmanya Shreepathi, Auteur ; Shrikant M. Naik, Auteur ; Mohan Rao Vattipalli, Auteur Année de publication : 2012 Article en page(s) : p. 411-422 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Humidité -- Absorption
Infiltration
Perméabilité
Revêtements -- Effets de l'humidité
Revêtements organiques
Spectroscopie d'impédance électrochimique
Vapeur d'eauIndex. décimale : 667.9 Revêtements et enduits Résumé : A primary cause of coating failure is diffusion of water through organic coatings during which many corrosive species are transported to the metal-coating interface. However, water vapor permeability through the coating improves blister resistance to a certain extent. The present work describes the influence of chemical nature of the polymer on the above two properties. Attempts were also made to establish a correlation between these two properties for pigmented organic coating. Six paints were formulated and processed using six different types of binders at a constant pigment volume concentration (PVC) and specific gravity. Water ingress, water vapor permeability, and water absorption of these coatings were estimated using electrochemical impedance measurements (EIS), permeability cup method, and gravimetric method, respectively. There exists a good linear correlation between water uptake measured by EIS and water absorption measured by gravimetry. Similarly, a correlation was also noticed between water uptake by EIS and water vapor permeability. However, polyurethane type polymers did not fit into this linear correlation. Furthermore, influence of the resin chemistry on anticorrosive properties of these coatings was also studied using EIS and salt spray exposure test. Among all polymers under investigation, acrylic polyol-based polyurethane has shown the lowest water uptake, higher impedance, better salt spray resistance but higher water vapor transmission rate. Note de contenu : - EXPERIMENTAL : Materials and reagents - Processing of paints - Characterization
- RESULTS AND DISCUSSION : Water uptake by EIS - Water vapor permeability - Water absorption measurements - Role of resin on corrosion protection performance - Salt spray exposure studiesDOI : 10.1007/s11998-011-9376-4 En ligne : https://link.springer.com/content/pdf/10.1007%2Fs11998-011-9376-4.pdf Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=15992
in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 9, N° 4 (07/2012) . - p. 411-422[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 14189 - Périodique Bibliothèque principale Documentaires Disponible