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.
| Original language | English |
|---|---|
| Pages (from-to) | 690-702 |
| Number of pages | 13 |
| Journal | Materials and Corrosion |
| Volume | 69 |
| Issue number | 6 |
| Early online date | 3 Jan 2018 |
| DOIs | |
| Publication status | Published - 1 Jun 2018 |
| MoE publication type | A1 Journal article-refereed |
Funding
Finnish Funding Agency for Technology and Innovation (Tekes) The work was carried out within the Digital, Internet, Materials, and Engineering Co-Creation (DIMECC) and its Breakthrough Steels and Applications (BSA) program. We gratefully acknowledge the financial support from the Finnish Funding Agency for Technology and Innovation (Tekes). We also want to thank the Oak Ridge National Laboratory and the Carpenter Technology Corporation for providing the AFA alloys and the Massachusetts Institute of Technology for providing the 12Cr2SiFe alloy for the study.
Keywords
- Al-alloyed
- crystal structure
- Ni-base alloy
- oxidation
- Si-alloyed
- stainless steel