Effect of biofouling on Corrosion behaviour of grade 2 titanium in Mandapam seawaters

Titanium has the abilit to withstand extremely high seawater velocities with negligible corrosion. The inherent passive nature of the metal favours the attachment ofbio-organisms more. In this paper the biofouling characteri tics and theinfluence ofmacrofouJing on grade2titanium havebeen investigated inthe Palk Baywaters ofMandapam (India) over a period ofa ycar.This work comprise both field exposure as well as laboratory studies. The deposits on titanium were analyzed with the XRD technique. Green algae such as Cladophorapsis zoolengeri, Cheatomorpha ar a hlorodeSlI/is hillibranclii, Entcromorphu intestinalis, Claclop~ora species and red algae species of Hypnea valentiae, and animals such as bryozoans and barnacles 4 rom in siz were identified on the titanium metal surface. Theeffect ofmacrofouling oncorrosionoftitaniumwas investigated bybothimpedanceandpolarizationtechniques. Titanium experienced negligible corrosion in seawater exposure with an appreciable fouling load of 0.4527 kg.m 2y I