Transformation of the δ-Ferrite in SS2343 Austenitic Stainless Steel upon Annealing at 1050 °C, 1150 °C and 1250 °C
| Autor: | Franci Vode, Boštjan Arh, Franc Tehovnik |
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| Rok vydání: | 2021 |
| Předmět: |
delta ferrite
Materials science Annealing (metallurgy) Analytical chemistry 02 engineering and technology engineering.material 01 natural sciences austenitic stainless steel Ferrite (iron) morphology 0103 physical sciences General Materials Science Austenitic stainless steel Dissolution 010302 applied physics Austenite Acicular Mining engineering. Metallurgy transformation TN1-997 Metals and Alloys 021001 nanoscience & nanotechnology Microstructure Volume fraction engineering annealing 0210 nano-technology |
| Zdroj: | Metals, Vol 11, Iss 935, p 935 (2021) Metals Volume 11 Issue 6 |
| ISSN: | 2075-4701 |
| DOI: | 10.3390/met11060935 |
| Popis: | The solidification behaviors of laboratory cast austenitic SS2343 stainless steel in terms of the volume fraction of δ-ferrite in the as-cast state and its transformation after subsequent annealing were investigated. Monitoring of morphological transformations of δ-ferrite in the microstructure show the progress of δ-ferrite dissolution. Annealing tests were conducted at 1050 °C, 1150 °C and 1250 °C with soaking times of 5 and 40 min. The thermodynamic prediction and metallographic identification of δ-ferrite are presented. The ferrite fractions were measured using a magnetic method and determined to be in the range between 10.7% and 14.6%. The volume share of δ-ferrite decreased with an increase in temperature and the time of annealing. About 50–55% the δ-ferrite was effectively transformed. The δ-ferrite phase, originally present in a dendritic morphology, tends to break up and spheroidize. The morphology varies from vermicular, lacy and acicular shapes to globular for higher temperatures and for longer exposure times. In the δ-ferrite after annealing, concentrations of Cr and Mo decrease, and conversely the concentration of Ni increase, all by small, but significant, amounts. The observed changes in the solute concentration can be explained in terms of the transformation of ferrite into austenite and sigma phases. |
| Databáze: | OpenAIRE |
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