<abstract xmlns="http://www.w3.org/1999/xhtml">The effects of chloride concentration, creviced scaling factor and immersion time on the percentage area and maximum depth of attack for Type 304 stainless steel (SS304) in chloride solutions were investigated. The crevice assembly comprised of coupon (SS-304), polytetrafluoroethylene (crevice former) and fasteners (titanium bolt, nut and washers). The full immersion tests were based on ASTM G-78 using full factorial design to study the effects of chloride concentration (1.5, 3.0 and 4.5 w/w%), crevice scaling factor (8, 16 and 24) and immersion time (15, 30 and 45 days) on the percentage area of attack (Y1) and maximum depth of attack (Y2) of SS-304. Data obtained was used to develop and optimize the models of Y1 and Y2 in terms of the three factors using Response Surface Methodology (RSM). The R2 of Y1 and Y2 were 0.98 and 0.91, respectively. The minimum Y1 (5.63%) and Y2 (3.32×10−7 mm) were obtained at 4.5% chloride concentration, 20 scaling factor and 15 days immersion time. The predicted optimal conditions agreed with the experimental results for validation with a maximum absolute relative error of 5.75%.</abstract>

The effects of chloride concentration, creviced scaling factor and immersion time on the percentage area and maximum depth of attack for Type 304 stainless steel (SS304) in chloride solutions were investigated. The crevice assembly comprised of coupon (SS-304), polytetrafluoroethylene (crevice former) and fasteners (titanium bolt, nut and washers). The full immersion tests were based on ASTM G-78 using full factorial design to study the effects of chloride concentration (1.5, 3.0 and 4.5 w/w%), crevice scaling factor (8, 16 and 24) and immersion time (15, 30 and 45 days) on the percentage area of attack (Y1) and maximum depth of attack (Y2) of SS-304. Data obtained was used to develop and optimize the models of Y1 and Y2 in terms of the three factors using Response Surface Methodology (RSM). The R2 of Y1 and Y2 were 0.98 and 0.91, respectively. The minimum Y1 (5.63%) and Y2 (3.32×10−7 mm) were obtained at 4.5% chloride concentration, 20 scaling factor and 15 days immersion time. The predicted optimal conditions agreed with the experimental results for validation with a maximum absolute relative error of 5.75%.

Factorial Design based Optimisation of Crevice Corrosion for Type 304 Stainless Steel in Chloride Solutions

Department of Chemical Engineering, Ladoke Akintola University of Technology, P.M.B. 4000, Ogbomoso, Nigeria.

Department of Chemical Engineering, University of Ilorin, Ilorin, Nigeria.

Department of Mechanical Engineering, Ladoke Akintola University of Technology, P.M.B. 4000, Ogbomoso, Nigeria

Advances in Materials Science

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The effects of chloride concentration, creviced scaling factor and immersion time on the percentage area and maximum depth of attack for Type 304 stainless...

Factorial Design based Optimisation of Crevice Corrosion for Type 304 Stainless Steel in Chloride Solutions

Published Online: Aug 02, 2016

Page range: 5 - 20

DOI: https://doi.org/10.1515/adms-2016-0005

Keywords
crevice corrosion, scaling factor, stainless steel, optimisation, chloride solution

© 2016 O.O. Ogunleye et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Factorial Design based Optimisation of Crevice Corrosion for Type 304 Stainless Steel in Chloride Solutions

Published Online: Aug 02, 2016

Page range: 5 - 20

DOI: https://doi.org/10.1515/adms-2016-0005

Keywordscrevice corrosion, scaling factor, stainless steel, optimisation, chloride solution

© 2016 O.O. Ogunleye et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
crevice corrosion, scaling factor, stainless steel, optimisation, chloride solution