Analysis of Ductile-Brittle Transition Temperatures for Controlled-Rolled, Microalloyed, C-Mn Based Steels.
Abstract
Charpy V-notch ductile-brittle transition temperatures reported for a conventional carbon manganese steel and for several controlled-rolled microalloyed steels are compared with transition temperatures computed on a dislocation model basis. The computed transition temperature, Tc, is specified by equating the tensile cleavage fracture stress and the effective yield stress at the Charpy V-notch. Increased friction stress resistances to dislocation movement provided by solutes, precipitates, and other dislocations raise the yield stress and, thereby, increase Tc. A residual dislocation based friction stress resistance occurs within untransformed ferrite grains (that is, the ferrite present at the rolling temperature) when finish rolling is done in the austenite-ferrite region. Grain size refinement normally lowers Tc because the cleavage stress is increased to a greater extent than is the yield stress. Keywords: Ductile-brittle transition temperature, C-Mn steel, Carbide plate effects. (jes)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1988
- Accession Number
- ADA198132
Entities
People
- G. R. Speich
- L. R. Link
- R. W. Armstrong