Creep Deformation Behaviour and its Effect on Creep Life and Rupture Ductility of W-Mo-balanced 9Cr Steels. (3rd May 2020)

• Record Type: Journal Article
• Authors: Abe, Fujio
• Is Part Of: Materials at high temperatures. Volume 37:Number 3(2020)
• Page Start: 165
• Page End: 177
• Publication Date: 2020-05-03
• Subjects: 9cr steel -- w-Mo balance -- time to rupture -- reduction of area -- transient creep region -- acceleration creep region -- creep rate -- minimum creep rate -- time to minimum creep rate -- strain to minimum creep rate; Materials at high temperatures -- Periodicals; High temperatures -- Periodicals; 620.1121705
• DOI: 10.1080/09603409.2020.1735208
• Languages: English
• ISSNs: 0960-3409

Abstract

ABSTRACT: The creep deformation behaviour and its effect on the creep life and rupture ductility are investigated for W-Mo-balanced 9Cr steels at 600 °C to 700 °C. The creep life is described as t r = 1.5/[ ε ˙ min ( d ln ε ˙ /d ε )], where ε ˙ min and d ln ε ˙ /d ε reflect the creep deformation behaviour in the transient and acceleration creep regions, respectively. The creep life is also correlated with the time to minimum creep rate t m as t r = gt m, where g slightly increases with decreasing stress. The logarithm of creep rate linearly increases with strain in the initial stage of acceleration creep region. This is followed by a decrease in d ln ε ˙ d ε with strain at high stresses, resulting in ductile failure at large strains, while it is followed by an increase in d ln ε ˙ /d ε with strain at low stresses, resulting in rupture at small strains.