As we know well, in general, the plastic deformation is equal to non-individual dislocations motion. So, any factor that can be play the role of obstacle against dislocations motion, can lead increasing in resistance to plastic deformation and increasing in yield strength value, consequently. Dislocation density enhancement is one of the most important factors that causes the increase in dislocations interaction and decrease in dislocations mean free path. In addition, you must consider that the yield strength is an intrinsic parameter ( nature of the material ) that has constant value at specified condition. The reason of the latter is determined potential for dislocation generation and exhaustion at each condition.
As we know well, in general, the plastic deformation is equal to non-individual dislocations motion. So, any factor that can be play the role of obstacle against dislocations motion, can lead increasing in resistance to plastic deformation and increasing in yield strength value, consequently. Dislocation density enhancement is one of the most important factors that causes the increase in dislocations interaction and decrease in dislocations mean free path. In addition, you must consider that the yield strength is an intrinsic parameter ( nature of the material ) that has constant value at specified condition. The reason of the latter is determined potential for dislocation generation and exhaustion at each condition.