According to the metallurgy point of view, how these mechanisms help into affects the behavior of materials' intrinsic property?
Do you want to know about their role on metal's intrinsic property or correlation between the two?
Zener pinning would hinder re-orientation of grains ( that is hindrance towards recrystallization and recovery), especially under load. That is, you may suppress dynamic recovery to some extent using this method. If antiphase or twin boundaries come into play, then their movement can be somewhat suppressed as well, thus it may have role on magnetism as well. Orowan bowing is important for over-aged, coarse-precipitate strengthened metallic system, as you may know.
Orowan looping is the dominant mechanism of dislocation circumventing a particle if its size is large (and the particle is hard, incoherent). Larger the particle, easier to "bow" across the particle (i.e. less stress required). Zener pinning pressure also decreases with radius rise. But note the obvious geometry- Particles are 3D, interfaces are 2D and dislocations are 1D. Trajectory of a 1D entity (curve) is 2D (surface) that can cut a 3D entity (solid) into two parts; but trajectory of a 2D entity (surface) is 3D that cannot "cut into two" another 3D object. So, cutting through smaller-size particles in case of extremely high Orowan stress is an alternate option-no such equivalent route alternative to Zener pinning is coming into my mind (you may find yourself).
If there is a large amount of dislocation inside a grain (heavily cold-worked) , then ratio of grain surface area to dislocation length it contains may be much smaller than dislocation length itself. This will indicate much more dislocation bowing than grain boundary migration across a particle; although if dislocations bunch into cells and subcells, then their boundaries might hold some interfacial energy, that may approach order of magnitude of surface energy of grain boundary. Thus an aggregate of dislocations will start to act as a "sheet", and Zener-Orowan forces would begin to merge with each other. If dislocations arrange themselves into slip bands, directionality would be even more prominent.
On the other hand, if one considers twinning to be a viable mode of deformation at very low strain level, and twin boundaries are supposed to be sufficiently mobile (twin boundaries can also be low or high-angle), then a particle would experience more crossing of interfaces than dislocations- although profuse crossing of twin boundaries (implying rather high deformation) with relative absence of dislocation is not very likely.
Massive transformation due to solid-state phase transition or order-disorder transition are much complicated issues with solid-state interface migration, and I do not have adequate knowledge on these topics.
Do you want to know about their role on metal's intrinsic property or correlation between the two?
Zener pinning would hinder re-orientation of grains ( that is hindrance towards recrystallization and recovery), especially under load. That is, you may suppress dynamic recovery to some extent using this method. If antiphase or twin boundaries come into play, then their movement can be somewhat suppressed as well, thus it may have role on magnetism as well. Orowan bowing is important for over-aged, coarse-precipitate strengthened metallic system, as you may know.
Orowan looping is the dominant mechanism of dislocation circumventing a particle if its size is large (and the particle is hard, incoherent). Larger the particle, easier to "bow" across the particle (i.e. less stress required). Zener pinning pressure also decreases with radius rise. But note the obvious geometry- Particles are 3D, interfaces are 2D and dislocations are 1D. Trajectory of a 1D entity (curve) is 2D (surface) that can cut a 3D entity (solid) into two parts; but trajectory of a 2D entity (surface) is 3D that cannot "cut into two" another 3D object. So, cutting through smaller-size particles in case of extremely high Orowan stress is an alternate option-no such equivalent route alternative to Zener pinning is coming into my mind (you may find yourself).
If there is a large amount of dislocation inside a grain (heavily cold-worked) , then ratio of grain surface area to dislocation length it contains may be much smaller than dislocation length itself. This will indicate much more dislocation bowing than grain boundary migration across a particle; although if dislocations bunch into cells and subcells, then their boundaries might hold some interfacial energy, that may approach order of magnitude of surface energy of grain boundary. Thus an aggregate of dislocations will start to act as a "sheet", and Zener-Orowan forces would begin to merge with each other. If dislocations arrange themselves into slip bands, directionality would be even more prominent.
On the other hand, if one considers twinning to be a viable mode of deformation at very low strain level, and twin boundaries are supposed to be sufficiently mobile (twin boundaries can also be low or high-angle), then a particle would experience more crossing of interfaces than dislocations- although profuse crossing of twin boundaries (implying rather high deformation) with relative absence of dislocation is not very likely.
Massive transformation due to solid-state phase transition or order-disorder transition are much complicated issues with solid-state interface migration, and I do not have adequate knowledge on these topics.
Dear Dr. Singh, the details about zener-pinning effect and Orowan strenghtening mechanisms (in carbon nanotube reinforced Al composite) are discussed in attached paper.
Dear Tanvir Singh
The following study could help as well for more details on the topic.
Regards
Hall-Petch Breakdown at Elevated Temperatures.
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