Corrosion Performance of Damaged Thermally Sprayed Aluminium in Synthetic Seawater at Different Temperatures
Author: Shiladitya Paul
This paper reports the corrosion performance of damaged thermally sprayed aluminium (TSA) in ASTM D1141 synthetic seawater at 5°C and ≈ 101.5°C (boiling seawater). This research is particularly relevant to subsea installations. Al was arc-sprayed on carbon steel and holidays exposing underlying steel amounting to 4-5% area of the samples were made. The corrosion potential of these samples when exposed to synthetic seawater was monitored. The corrosion potential initially became more electronegative, reached a minimum and then became less electronegative to give values of −970 mV and −840 mV at 5°C and ≈ 101.5°C, respectively after 1200 hours. The corrosion rate was calculated to be ≈ 5-10 μm/y after 1200 h of exposure at both temperatures. The exposed steel was covered by a scale which led to the reduction in corrosion rate. The scale had a two-layer structure, Mg-containing close to and Ca-rich away from the substrate, at 5°C and only brucite [Mg(OH)2] at ≈ 101.5°C.
Pages: 139 - 146
![Ausgabe 2 (2015) Jahrgang 8 Page 139](https://contenthub.dvs-media.eu/storage/magazine-thumbnails/tspray/ausgabe-2-2015/139.jpg)
![Ausgabe 2 (2015) Jahrgang 8 Page 140](https://contenthub.dvs-media.eu/storage/magazine-thumbnails/tspray/ausgabe-2-2015/140.jpg)
![Ausgabe 2 (2015) Jahrgang 8 Page 141](https://contenthub.dvs-media.eu/storage/magazine-thumbnails/tspray/ausgabe-2-2015/141.jpg)
![Ausgabe 2 (2015) Jahrgang 8 Page 142](https://contenthub.dvs-media.eu/storage/magazine-thumbnails/tspray/ausgabe-2-2015/142.jpg)
![Ausgabe 2 (2015) Jahrgang 8 Page 143](https://contenthub.dvs-media.eu/storage/magazine-thumbnails/tspray/ausgabe-2-2015/143.jpg)
![Ausgabe 2 (2015) Jahrgang 8 Page 144](https://contenthub.dvs-media.eu/storage/magazine-thumbnails/tspray/ausgabe-2-2015/144.jpg)
![Ausgabe 2 (2015) Jahrgang 8 Page 145](https://contenthub.dvs-media.eu/storage/magazine-thumbnails/tspray/ausgabe-2-2015/145.jpg)
![Ausgabe 2 (2015) Jahrgang 8 Page 146](https://contenthub.dvs-media.eu/storage/magazine-thumbnails/tspray/ausgabe-2-2015/146.jpg)
Order this article as a PDF for 8.00 Euro. Send us a short e-mail with your details.
An active subscription enables you to download articles or entire issues as PDF-files. If you already are a subscriber, please login. More information about the subscription