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Crystallography. H. K. D. H. Bhadeshia. Introduction and point groups Stereographic projections Low symmetry systems Space groups Deformation and texture Interfaces, orientation relationships Homogeneous deformations Slip, twinning and invariant-plane strains. v. u. v. A. u. B.
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Crystallography H. K. D. H. Bhadeshia Introduction and point groups Stereographic projections Low symmetry systems Space groups Deformation and texture Interfaces, orientation relationships Homogeneous deformations Slip, twinning and invariant-plane strains
v u v A u B Similarity transformation
homogeneous deformation leaves points originally in a line, colinear, and lines originally in a plane, coplanar
general invariant-plane strain simple shear uniaxial dilatation s s d d 1 1 1 s=0.26 d=0.03
Refinement of austenite grain size • repeated recrystallisation • pancaking • Refinement of ferrite grain size • nucleation and growth
courtesy Rongshan Qin, GIFT, POSTECH Singh & Bhadeshia, 1998
v = Su u v
Cross Rolling second pass rotate 90° x first pass y y x