Investigations on coarsening of MX and M23C6 precipitates in 12% Cr creep resistant steels assisted by computational thermodynamics

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Structural materials : properties, microstructure and processing, 2010-08, Vol.527 (21-22), p.5976-5983
• Main Authors: PRAT, O, GARCIA, J, ROJAS, D, CARRASCO, C, KAYSSER-PYZALLA, A. R
• Format: Article
• Language: English
• Subjects: Chromium; Coarsening; Computer simulation; Creep (materials); Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Laves phase; Materials science; Phase diagrams and microstructures developed by solidification and solid-solid phase transformations; Physics; Precipitates; Precipitation; Scanning transmission electron microscopy
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2010.05.084

Coarsening of MX and M23C6 precipitates in two 12% Cr high alloyed steels have been investigated at creep conditions of 650A degree C, 100MPa up to 10,000h. The evolution of precipitates at different creep times was determined experimentally using scanning transmission electron microscopy (STEM). Phase equilibria were calculated with Thermocalc and simulations of coarsening of precipitates were carried out with Dictra. Both the STEM measurements as well as kinetic simulations indicate very low coarsening rates for MX and M23C6 precipitates. Dictra simulations showed a reduced influence of Laves phase and Z-phase formation on coarsening of M23C6.