Intro to Austenite 图 上唐东大学 In Fe-C system:austenite solid solution of C in fcc Fe Interstices in FCC structure. (a)Octahedral void. v (b)Tetrahedral void. (a) (b) ●Regular site atoms K.Chen 8 8
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Intro to Austenite 国 上清东通大学 In Fe-C system:austenite solid solution of C in fcc Fe All octahedral interstices occupied? →50at%C,or.20wt%C →Maximum2.11wt%C →Therefore,NoI →The maximum is10at%C 0.364 0.362 Fe●C Because: GHAI JIAO 0.360- >Radius of C is 0.77A 0.358 >Radius of octahedral site is 0.52A >Lattice distortion>100%occupied 0.356 impossible Lattice parameter 0 0.5 1.01.5 2.0 increase C Concentration/% K.Chen 9 9
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