Effect of annealing twins on Hall–Petch relation in polycrystalline materials

We analyze theoretically, how the annealing twin boundaries formed in a material during grain growth, affect its yield stress. For this propose, the twin boundary was considered as a barrier to dislocation motion as in case of grain boundaries. The Hall–Petch relation gets modified due to the presence of twin boundaries. This relation is shown to be in good fit for the only available experimental result. Our analysis also indicates that Hall–Petch relation is more likely to be due to grain boundaries as a dislocation barrier rather than as a dislocation source.