Static recovery of tempered lath martensite microstructures during long-term aging in 9-12% Cr heat resistant steels

摘要

Static recovery of tempered lath martensite microstructures of strength enhanced ferritic steels has been investigated during very long-term aging up to 2 × 10~4h at 650℃ for 3 steels containing 9 to 12% Cr. Static recovery of tempered lath martensite microstructure occurs after an incubation period for 1-2 × 10~3 h in the steels. The static recovery is controlled by the loss of strengthening due to M_(23)C_6 precipitates, and disappearance of MX carbonitrides cannot be the main cause of the static recovery.