A theory for steady state creep based on the motion of interstitial type jogs

✍ Scribed by Mahendra Malu; John K Tien

• Publisher: Elsevier Science
• Year: 1974
• Weight: 950 KB
• Volume: 22
• Category: Article
• ISSN: 0001-6160
• DOI: 10.1016/0001-6160(74)90004-2

✦ Synopsis

an activation energy for creep that is the same as that for vacancy self-diffusion.

Activation energy values corresponding to those for vacancy selfdiffusion are indeed observed for the creep of pure metaM2* 7-121 and for single phase alIoys.(is* 14) However, activation energies much higher than those for vacancy self-diffusion, first reported by Ansell and Weertman,@' are now commonly observed for creep of particle st.rengthened systems.(i"**l This phenomenon appears to be independent of whether the creep process involves dislocation bowing between t,he particles, as in inert dispersion strengthened systems,(15* ls) or passing through the stren~he~ng particles, as in nickel-base superalloy-s containing high volume fraction of fine y' precipitates,c2'* 24) and it is not related to grain boundary creep processes, since high activation energies are also obsemed during the steady state creep of monocrystahine nickeLbase ACT.4 11 2