a b prism hcp 13 Dislocation Density Characteristics 200 nm Dislocation density

A b prism hcp 13 dislocation density characteristics

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a b prism hcp 13 Dislocation Density & Characteristics 200 nm Dislocation density ( ) : Length of dislocation line per unit volume ( cm/cm 3 ) ; Avg. spacing ≈1/ Example : Dislocation density in high strength steel 10 12 cm/cm 3 Dislocation density in Si used in IC 1-10 cm/cm 3 TEM photomicrograph of dislocations in Ni-base superalloy Rules : Dislocations do not end inside the crystal; hence, dislocation loops inside An edge dislocation is perpendicular to b (Burgers vector) Edge dislocation moves in slip plane in the direction of b A screw dislocation is parallel to b Screw dislocation moves in slip plane perpendicular to b Edge dislocation movement is confined in a unique plane Screw dislocation can glide in any direction, as long as it moves parallel to its original direction, hence, cross slip 14
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