Creep deformation behaviour and kinetic aspects of 9Cr-1Mo ferritic steel

Citation
Bk. Choudhary et al., Creep deformation behaviour and kinetic aspects of 9Cr-1Mo ferritic steel, ISIJ INT, 41, 2001, pp. S73-S80
Citations number
26
Categorie Soggetti
Metallurgy
Journal title
ISIJ INTERNATIONAL
ISSN journal
09151559 → ACNP
Volume
41
Year of publication
2001
Supplement
S
Pages
S73 - S80
Database
ISI
SICI code
0915-1559(2001)41:<S73:CDBAKA>2.0.ZU;2-E
Abstract
This paper presents the detailed investigations on creep behaviour of 9Cr-1 Mo ferritic steel with an emphasis to understand and unify the different st ages of creep deformation in the framework of first order kinetic approach. The different values of stress exponent and apparent activation energy obs erved for the two stress regimes have been rationalized by invoking the con cept of resisting stress. The detailed analysis of results revealed that bo th transient and tertiary creep obeyed first order kinetics with separate v alues of transient and tertiary creep parameters in the respective stress r egimes. The two stress regimes with different values of stress exponent are manifested as separate master creep curves for transient and steady state creep. Similarly, the analysis of tertiary creep also revealed distinct mas ter creep curves relating steady state and tertiary creep in the respective stress regimes. The paper also focuses attention on two important relation ships, one obtained between transient and steady state creep, and the other between steady state and tertiary creep. The useful implications of these relationships in understanding the existing creep rate-rupture life relatio nships of Monkman-Grant type are also highlighted in this paper.