This indicates that as the grain size drops below the grain boundary strengthening limit, a smaller grain size would suppress the formation of dislocation pile-ups and instead promotes more grain boundary diffusion and sliding, which resolves the applied stress and in turn reduces the material's yield strength.
Based on the results of the hierarchical structure characterizations, not only increase in crystallinity but also formation of the strengthened interspherulitic boundaries is the possible origin of the significant improvement of the mechanical properties of the gels annealed near Tm.
The short equilibrium M-B (M = Nb, Ta, Mo or W) bonds induce local contractions around grain boundaries, which in turn strengthens grain boundaries remarkably, thereby enhances the mechanical properties of ZrB2 at evaluated temperatures.
Forgiveness is not the relaxing of a boundary; if anything, forgiveness builds and strengthens healthy boundaries.
It is found that the interfacial fracture energy between SiC and alumina is more than twice the alumina grain boundary fracture energy, i.e. SiC nanoparticles strengthen grain boundaries.
The facts and appearances of this case strongly suggest that The Times should redouble its efforts to strengthen the boundaries that are so essential to cultivating reader trust.
The hardness was influenced by the amorphous yttrium oxide phase, solid solution strengthening, grain boundaries and residual stress.
The possible reason as suggested by Kurishita et al. [14] is that the addition of TiC and the recrystallization of W TiC alloy result in much efficient packing of the grains and strengthening grain boundaries.
But the student body that produced a prize-winning academic thesis claiming that IDF soldiers' lack of rape of Palestinian women is just as degrading as if they had raped them, because the lack of rape "strengthens ethnic boundaries" (I'm not kidding--and the best part, I think, is that it won a prize) seems to me to have some issues to work out on its own.
In particular, these include precipitate and grain boundary strengthening, low-angle boundary dislocation annihilation and martensitic lath width evolution, using dislocation density as a key variable.
