The influence of annealing in the ferrite-plus-austenite phase field on the stability of vanadium carbide precipitates
| Autor: | Gary M. Michal, I.E. Locci |
|---|---|
| Rok vydání: | 1989 |
| Předmět: | |
| Zdroj: | Metallurgical Transactions A. 20:237-245 |
| ISSN: | 2379-0180 0360-2133 |
| DOI: | 10.1007/bf02670249 |
| Popis: | The influence of rapid excursions into the ferrite-plus-austenite two-phase field on V4C3 precipitates formed by tempering in the ferrite phase was explored. The iron-based alloy studied contained 0.14 carbon and 0.49 vanadium in wt pct. A fine distribution of V4C3 particles was obtained through solution treatment followed by quench and tempering at 973 K. Samples were then rapidly heated to 1088 K for various times between 50 and 300 seconds. The plate-shaped V4C3 precipitates in regions that maintained their original ferrite matrix exhibited a continuous coarsening and decrease in their aspect ratio with increasing hold times. The V4C3 precipitates in regions that transformed to austenite were observed to dissolve by a reversion process if they were below a certain size. If the V4C3 particles were above that size, the matrix change caused them to coarsen and reduce their aspect ratio. Based upon the size of V4C3 particles that did show reversion, the interphase interfacial surface energy between the V4C3 partieles and aus tenite in the nonequilibrium orientation relationships produced in this study was determined to be between 1125 and 1840 mJ/m2. When samples where reversion was observed were retempered at 973 K, the original distribution of fine, plate-shaped V4C3 particles could be reproduced accompanied by a measurable secondary hardening response. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|