Oxide Spallation During Post-isothermal High Temperature Oxidation Cooling of Cr-rich Cast Alloys Highly Alloyed with Hf
Elodie Conrath, Patrice Berthod*
Identifiers and Pagination:Year: 2016
First Page: 89
Last Page: 100
Publisher Id: TOMSJ-10-89
Article History:Received Date: 18/8/2015
Revision Received Date: 10/10/2015
Acceptance Date: 11/11/2015
Electronic publication date: 30/09/2016
Collection year: 2016
open-access license: This is an open access article licensed under the terms of the Creative Commons Attribution-Non-Commercial 4.0 International Public License (CC BY-NC 4.0) (https://creativecommons.org/licenses/by-nc/4.0/legalcode), which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.
Cobalt, nickel and iron-based alloys containing 25wt.%Cr and strengthened either by chromium carbides or by HfC were oxidized at 1000, 1100 and 1200°C to obtain external oxide scales. The spallation of these oxides during the post-oxidation cooling was studied by exploiting the cooling part of the thermogravimetry curves. The best resistant alloys against scale spallation were the iron-based alloys which did not lose oxide. The nickel-based alloys well behaved too. The worst alloys were the cobalt alloys, principally due to the complex composition of the oxide scales. Beside the base element, the thickness of the oxide was also identified as a major parameter. The presence of Hf with contents much higher than usual was also beneficial for the resistance against spallation.