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J. Shim, E. Kozeschnik, W. Jung, Y. Cho:
"Prediction of long-term precipitate evolution in austenitic heat-resistant steels";
Talk: Liege Conference: Materials for Advanced Power Engineering 2010, Liege, Belgium; 09-27-2010 - 09-29-2010; in: "Materials for Advanced Power Engineering 2010", (2010), 198 - 207.

Numerical prediction of the long-term precipitate evolution in five different austenitic heat-resistant stainless
steels, NF709, Super304H, Sanicro25, CF8C-PLUS and HTUPS has been carried out. MX and M23C6 are
predicted to remain as major precipitates during long-term aging in these steels. The addition of 3 wt% Cu
produces very fine Cu-rich precipitates during aging in Super304H and Sanicro25. It is found that the amount of
Z phase start to increase remarkably between 1,000 and 10,000 hours of aging at the expense of MX precipitates
in the steels containing a high nitrogen content. However, the growth rate of Z phase is relatively slow and its
average size reaches at most a few tens of nanometers after 100,000 hours of aging at 700 oC, compared with 9-
12 % Cr ferritic/martensitic heat-resistant steels. The predicted precipitation sequence and precipitate size during
aging are in general agreement with experimental observations.