A diffraction study of the annealing of cold-worked Cu 3 Au
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p a s s a g e of a n o r m a l fcc d i s l o c a t i o n ( B u r g e r s v e c t o r a//2 [[110]]) on the ((111)) s l i p p l a n e p r o d u c e s A P D B . 1 The o r d e r i n g b e h a v i o r of c o l d - w o r k e d Cu3Au w a s f i r s t s t u d i e d by J o n e s and S y k e s e using X - r a y f i l m t e c h n i q u e s . T h e y c o n c l u d e d f r o m m e a s u r e m e n t s of the p r o g r e s s of o r d e r i n g at 376~ that, c o n t r a r y to t h e i r e x p e c t a t i o n s , o r d e r i n g p r o c e e d e d m o r e s l o w l y in the i n i t i a l l y c o l d - w o r k e d a l l o y a s c o m p a r e d to t h e a l l o y t h e r m a l l y d i s o r d e r e d by quenching. Although c o m p l e t e e x p e r i m e n t a l d e t a i l s of t h e i r w o r k a r e not a v a i l a b l e , it w i l l be shown h e r e that t h e i r c o n c l u s i o n i s i n c o r r e c t b e c a u s e no c o r r e c t i o n w a s m a d e f o r the e f f e c t s of s t r a i n on the s u p e r l a t t i c e d i f f r a c t i o n p e a k s . When the s t r a i n c o r r e c t i o n i s m a d e , one finds the i n i t i a l l y e x p e c t e d r e s u l t ; i . e . , d o m a i n growth p r o c e e d s m o r e r a p i d l y in the i n i t i a l l y c o l d - w o r k e d a l l o y . The i s o t h e r m a l a n n e a l i n g b e h a v i o r of Cu3Au i n i t i a l l y in the t h e r m a l l y d i s o r d e r e d , o r d e r e d c o l d - w o r k e d , and d i s o r d e r e d c o l d - w o r k e d s t a t e s h a s a l s o been s t u d i e d by R o e s s l e r et al.~ They c o n c l u d e d f r o m m e a s u r e m e n t s of c h a n g e s in e l e c t r i c a l r e s i s t i v i t y at 288 ~ 310 ~
Fig. 1--((100)) Type I APDB in Cu3Au; after P. A. Flinn: Trans. TMS-AL~IE, 1960, vol. 218, p. 145. VOLUME 3, JUNE 1972-1479
and 340~ that the growth of a n t i p h a s e d o m a i n s i s i m peded in the i n i t i a l l y c o l d - w o r k e d s t a t e s a s c o m p a r e d to the t h e r m a l l y d i s o r d e r e d s t a t e . However, t h e i r l i m ited m e a s u r e m e n t s of domain s i z e s by X - r a y d i f f r a c tion f o r the s p e c i m e n s a n n e a l e d at 288~ showed the d o m a i n s to grow f a s t e r in the i n i t i a l l y c o l d - w o r k e d a l l o y s . T h i s d i s c r e p a n c y was explained on the b a s i s that had the a n n e a l i n g been c a r r i e d f u r t h e r at 288~ the growth would have b e e n i n h i b i t e d . The r e s u l t s to be r e p o r t e d h e r e will show that this i s not the c a s e and that the d o m a i n s continue to be l a r g e r in the i n i t i a l l y c o l d - w o r k e d alloy as c o m p a r e d to the i n i t i a l l y quenched alloy. Cahn and A r u n a c h a l a m 6 concluded that r e c r y s t a l l i z a tion below T c in c o l d - w o r k e d Cu3Au is h i n d e r e d by the o r d e r i n g p r o c e s s . They c o m p a r e d X - r a y and m i c r o h a r d n e s s data for s a m p l e s r e c r y s t a l l i z e d j u s t above and bel
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