Galvanic interactions of HE15 /MDN138 & HE15 /MDN250 alloys in natural seawater
- 33 Downloads
HE15 is a heat treatable high strength alloy with excellent machinability find wide applications in aerospace and defence industries. In view of their excellent mechanical properties, workability, machinability, heat treatment characteristics and good resistance to general and stress corrosion cracking, MDN138 & MDN250 have been widely used in petrochemical, nuclear and aerospace industries. The galvanic corrosion behaviour of the metal combinations HE15 /MDN138 and HE15 /MDN250, with 1:1 area ratio, has been studied in natural seawater using the open well facility of CECRI’s Offshore Platform at Tuticorin for a year. The open circuit potentials of MDN138, MDN250 and HE15 of the individual metal, the galvanic potential and galvanic current of the couples HE15 /MDN138 and HE15 /MDN250 were periodically monitored throughout the study period. The calcareous deposits on MDN138 and MDN250 in galvanic contact with HE15 were analyzed using XRD. The electrochemical behaviors of MDN138, MDN250 and HE15 in seawater have been studied using an electrochemical work station. The surface characteristics of MDN138 and MDN250 in galvanic contact with HE15 have been examined with scanning electron microscope. The results of the study reveal that HE15 offered required amount of protection to MDN138 & MDN250.
Keywordsalloy MDN138 MDN250 HE15 galvanic corrosion natural seawater
Unable to display preview. Download preview PDF.
The authors wish to thank the Director, The CSIR-Central Electrochemical Research Institute, Karaikudi, for permission and encouragements.
- ASTM International, 2011. Standard practice for preparing, cleaning, and evaluating corrosion test coupons. ASTM standards, ASTM International, West Conshohocken, Designation G1-03.Google Scholar
- Culberson CH, 1983. Effect of seawater chemistry on the formation of calcareous deposits. Corrosion 1983, Houston, Paper No. 61.Google Scholar
- Edyvean RGJ, 1987. Interactios between microfouling and the calcareous deposit formd on cathodically protected steel in seawater. 6th Intl Cong Marine Corrosion and Fouling, Vol: Marine Biology, Athens, 469–475.Google Scholar
- Hack HP, Guanti RJ, 1989. Effect of high flow on calcareous deposits and cathodic protection current density. Materials Performance, 28(3), 29–35.Google Scholar
- ASM, 1981. Exfoliation corrosion of HE.15 aluminium alloy. In Failure analysis: The British Engine Technical Reports, F.R. Hutchings and P.M. Unterweiser Ed., American Society for Metals.Google Scholar
- Hutchings FR, Unterweiser PM, 1981. Exfoliation corrosion of HE.15 aluminium alloy. In Failure analysis: The British Engine Technical Reports, American Society for Metals.Google Scholar
- Kciuk M, Tkaczyk S, 2007. Structure, mechanical properties and corrosion resistance of AlMg5 and AlMg1Si1 alloys. Journal of Achievements in Materials and Manufacturing Engineering, 21(1), 39–42.Google Scholar
- Kunjapur M, Hartt W, Smith S, 1985. Influence of temperature on calcareous deposition cathodically polarized steel in seawater. Corrosion 1985, Houston, Paper No. 316.Google Scholar
- Lee R, Ambrose J, 1986. A hydrodynamical and chemical study of calcareous deposits. Corrosion 1986, Houston, Paper No. 292.Google Scholar
- Little BJ, Wagner PA, 1993. The interrelationship between marine biofouling and cathodic protection. Corrosion 1993, Houston, Paper No. 525.Google Scholar
- Liu H, 2015. Mechanical properties and corrosion behaviors of novel Cr2Ni Low-alloy construction steel. International Journal of Electrochemical Science, 10(3), 2130–2140Google Scholar
- Osorio RW, Noe C, Peixoto CL, Amauri G, 2009. Corrosion resistance and mechanical properties of an Al 9wt% Si alloy treated by laser surface remelting. International journal of electrochemical science, 4(6), 820–831.Google Scholar
- Sarlak M, Shahrabi T, Zamanzade M, 2009. Investigation of calcareous deposits formation on copper and 316L stainless steel under cathodic polarization in artificial seawater. Protection of Metals and Physical Chemistry of Surfaces, 45(2), 216–222. DOI: 10.1134/S2070205109020166CrossRefGoogle Scholar
- Strickland JDH, Parsons TR 1972. A practical handbook of seawater analysis. Fisheries Research Board of Canada, Ottawa, 310.Google Scholar
- Wieng SM, Osvoll H, Gartland PO, 2007. Efficient cathodic protection to stainless steel small bore tubing. Corrosion 2007, Houston, Paper No. 07078.Google Scholar