Journal Published Online: 01 January 1988
Volume 16, Issue 1

Diametral Strain Response and Microstructural Yielding Mechanisms of a Bainitic Pressure Vessel Steel



Unexpected trends of diametral strain range response have been recorded for annealed bainitic Cr-Mo-V-pressure vessel steel at room temperature and moderate strain amplitudes. Stress and diametral strain response were also recorded for three harder heat treatment variants, but they behaved as expected. The alloy is strengthened by a carbide dispersion and a dislocation network, both of variable density. The unexpected diametral strain response is suggested to be associated with yet unknown macroscopic effects of particular observed microscopic mechanisms of slip. These mechanisms of slip can be analyzed with a model for dispersion strengthening which expresses the connection between nominal dislocation activity and the plastic and elastic components of elongation. The necessity for a differentiation between effective obstacles to slip consisting of stable carbides or cyclically unstable dislocation networks is arrived at. Observation of slip mechanisms by scanning electron microscopy is presented.

Author Information

Rahka, KA
Technical Research Centre of Finland, Espoo, Finland
Solin, JP
Technical Research Centre of Finland, Espoo, Finland
Kemppainen, MJ
Technical Research Centre of Finland, Espoo, Finland
Pages: 15
Price: $25.00
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Stock #: JTE11051J
ISSN: 0090-3973
DOI: 10.1520/JTE11051J