GbL as L ie The longest segments operate first When the long segments get

Gbl as l ie the longest segments operate first when

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~ Gb/L   ↓ as L↑ i.e. The longest segments operate first When the long segments get immobilized shorter segments operate with increasing stress work hardening If the dislocation loops keep piling up on the slip plane the back stress will oppose the applied stress. When the back-stress > max the source will cease to operate
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Let us consider the various ways of understanding the dislocation The different perspectives Association with translational symmetry As a line defect Distortion of bonds → region of high energy Increase in entropy of the system Free volume at the core → pipe diffusion Core of dislocation & its geometry → Peierls Stress Stress & Strain fields Interaction with other defects Role in slip Mental Picture of a dislocation
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