3D Discrete Dislocation Dynamics: Influence of Segment Mobility on Critical Shear Stress

0451515 - ÚFM 2016 RIV PL eng J - Článek v odborném periodiku
Záležák, Tomáš - Dlouhý, Antonín
3D Discrete Dislocation Dynamics: Influence of Segment Mobility on Critical Shear Stress.
Acta Physica Polonica A. Roč. 128, č. 4 (2015), s. 654-656. ISSN 0587-4246. E-ISSN 1898-794X.
[ISPMA 13 - International Symposium on Physics of Materials /13./. Praha, 31.08.2014-04.09.2014]
Grant CEP: GA MŠMT(CZ) EE2.3.20.0214; GA ČR(CZ) GA14-22834S
Institucionální podpora: RVO:68081723
Klíčová slova: metal matrix composites * discrete dislocation dynamics * high temperature creep
Kód oboru RIV: JG - Hutnictví, kovové materiály
Impakt faktor: 0.525, rok: 2015

We use 3D discrete dislocation dynamics technique to study a low-angle tilt boundary migration subjected to applied shear stress at high temperatures, where di usion signi cantly contributes to the dislocation motion. The model considers Peach Koehler forces due to interactions between individual straight dislocation segments. The model also addresses dislocation plasticity in a eld of impenetrable incoherent spherical precipitates. Velocities of the individual dislocation segments are calculated in relation to the crystallography of the material. Several calculation series have been carried out for di erent velocity and driving force relations. The results show that there exists a critical applied shear stress, below which the low angle dislocation boundary cannot surpass the rigid precipitates and remains in an equilibrium con guration. This agrees with experimental results obtained in creep tests of dispersion strengthened alloys. The critical stresses have been calculated also for situations where the applied stress was decreased during the interaction between the low-angle tilt boundary and the precipitates
Trvalý link: http://hdl.handle.net/11104/0252653