Publication details
Phase changes in superaustenitic steels after long-term annealing
| Authors | |
|---|---|
| Year of publication | 2004 |
| Type | Article in Periodical |
| Magazine / Source | Zeitschrift fur Metallkunde |
| MU Faculty or unit | |
| Citation | |
| Field | Physical chemistry and theoretical chemistry |
| Keywords | Austenitic steels; Microstructure; Thermodynamic modelling; Calphad method |
| Description | A structural study was performed on the austenitic steels Avesta 254 SMO and Avesta 654 SMO after annealing at 700 C for 500, 3188 and 6170 h. Both Avesta steels initially show an unexpectedly large amount of the Laves phase, followed by a relative slow development of the Sigma phase with equilibrium apparently not yet reached after 3188 h. Thermodynamic calculations confirm that the driving forces for alternative precipitates are very similar thus making it easy to form metastable precipitates that only change very slowly to the equilibrium state. TTT calculations also comnfirm that the Laves phase precipitates earlier than the Sigma phase as the temperature is lowered. |