Yield Stress and Particle Size

0is the temperature, k is Boltzmann s constant and V is the volume of the dislocation core. 

This result gives the dependence of crystal yield strength on particle size and work hardening due to the creation and movement of N dislocations during plastic flow. In the limit of small particle size, 20 microns, where typically dUo/dx (N d)r Uo and the third order correction term is small, the yield stress behaves as Ty Nj if. This prediction accounts for the observed increased yield strength of small crystals and forms the basis of the specialty iron and steel industry [26.27], It is also likely to be the reason why the shock and impact sensitivity decrease with crystal size as.  

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