Carbides Evolution in a Ni-16Mo-7Cr Base Superalloy during Long-Term Thermal Exposure
نویسندگان
چکیده
The effect of long-term thermal exposure on the carbide evolution in a Ni-16Mo-7Cr base superalloy was investigated. The results show that M12C carbides are mainly precipitated on the grain boundaries during thermal exposure, and the primary massive M₆C carbides can be completely transformed to M12C carbides in situ at temperatures above 750 °C for long-term thermal exposure. The transformation from M₆C carbides to M12C carbides is attributed to the release of C atoms from M₆C, which results in the morphology changes of massive carbides, and stabilization of the sizes of M12C carbides precipitated on the grain boundaries.
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