Early stage oxidation behavior of Al- and Si-alloyed stainless steels as well as Ni-based alloys in air at elevated temperatures

Research output: Contribution to journalArticleScientificpeer-review

Researchers

Research units

  • University of Helsinki

Abstract

Several alloys including Al-alloyed austenitic and ferritic stainless steels, Ni-based alloy and Si-alloyed ferritic stainless steel were annealed at 550, 750, and 950 °C for up to 700 h. AISI 347HFG and 10CrMo910 were used as reference materials. Weight gain was measured and the samples were analyzed with SEM/EDS and XRD. Materials having high enough Al-content performed best due to ability to form a continuous protective Al2O3-oxide layer on their surface at elevated temperatures. Lower Al-content materials were not able to form a continuous protective Al-oxide on their surface and suffered from accelerated internal Al-oxide formation due to alloying elements. Si-alloying improves the oxidation resistance of the studied materials and their performance was practically in the same level as that of the best Al-alloyed materials. In Al-alloyed materials the crystallinity of Al2O3 on ferritic stainless steel weld metal was higher than that on welded and wrought austenitic stainless steels.

Details

Original languageEnglish
Pages (from-to)690-702
Number of pages13
JournalMaterials and Corrosion
Volume69
Issue number6
Early online date3 Jan 2018
Publication statusPublished - 1 Jun 2018
MoE publication typeA1 Journal article-refereed

    Research areas

  • Al-alloyed, crystal structure, Ni-base alloy, oxidation, Si-alloyed, stainless steel

ID: 17082321