Author: R. L. BrazillPublisher:
ISBN:
Category :
Languages : en
Pages : 8
Book Description
Fatigue Crack Growth in 2-1/4Cr-1Mo Steel Exposed to Hydrogen Containing Gases
Author: R. L. BrazillEnergy Research Abstracts
Author: Paper
Author: Publisher:
ISBN:
Category : Mechanical engineering
Languages : en
Pages : 774
Book Description
ASME Technical Papers
Author: Publisher:
ISBN:
Category : Mechanical engineering
Languages : en
Pages : 626
Book Description
Influences of Gaseous Environment on Low Growth-rate Fatigue Crack Propagation in Steels. Annual Report No. 1, January 1980. Report No. FPL/R/80/1030
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The influence of gaseous environment is examined on fatigue crack propagation behavior in steels. Specifically, a fully martensitic 300-M ultrahigh strength steel and a fully bainitic 2-1/4Cr-1Mo lower strength steel are investigated in environments of ambient temperature moist air and low pressure dehumidified hydrogen and argon gases over a wide range of growth rates from 10−8 to 10−2 mm/cycle, with particular emphasis given to behavior near the crack propagation threshold .delta.K0. It is found that two distinct growth rate regimes exist where hydrogen can markedly accelerate crack propagation rates compared to air, (1) at near-threshold levels below (5 x 10−6 mm/cycle) and (2) at higher growth rates, typically around 10−5 mm/cycle above a critical maximum stress intensity K/sub max//sup T/. Hydrogen-assisted crack propagation at higher growth rates is attributed to a hydrogen embrittlement mechanism, with K/sub max//sup T/ nominally equal to K/sub Iscc/ (the sustained load stress corrosion threshold) in high strength steels, and far below K/sub Iscc/ in the strain-rate sensitive lower strength steels. Hydrogen-assisted crack propagation at near-threshold levels is attributed to a new mechanism involving fretting-oxide-induced crack closure generated in moist (or oxygenated) environments. The absence of hydrogen embrittlement mechanisms at near-threshold levels is supported by tests showing that .delta.K0 values in dry gaseous argon are similar to .delta.K0 values in hydrogen. The potential ramifications of these results are examined in detail.
Journal of Engineering Materials and Technology
Author: Damage Mechanisms and Life Assessment of High Temperature Components
Author: Ramaswamy ViswanathanPublisher: ASM International
ISBN: 9780871703583
Category : Science
Languages : en
Pages : 497
Book Description
Author: 
Author: C. A. Hippsley
Author: