Recrystallization of low-carbon titanium stabilized steel
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The r e c r y s t a l l i z a t i o n k i n e t i c s and m i c r o s t r u c t u r e of a l o w - c a r b o n t i t a n i u m s t a b i l i z e d s t e e l , cold r o l l e d and a n n e a l e d in the t e m p e r a t u r e i n t e r v a l b e t w e e n 800 ~ and 1750~ w e r e i n v e s t i g a t e d . R e c r y s t a l l i z a t i o n f o l l o w e d the n o r m a l s i g m o i d a l r e l a t i o n s h i p at a l l t e m p e r a t u r e s ; h o w e v e r , c o m p a r e d to l o w - c a r b o n s t e e l without the a d d i t i o n of t i t a n i u m , r e c r y s t a l l i z a t i o n was s e v e r e l y r e t a r d e d . The l o n g e r t i m e r e q u i r e d f o r r e c r y s t a l l i z a t i o n is b e l i e v e d to have o c c u r r e d p r i m a r i l y a s a r e s u l t of the t i t a n i u m in s o l u t i o n and to a l e s s e r d e g r e e b e c a u s e of the p r e s e n c e of n u m e r o u s s t a b l e p r e c i p i t a t e p a r t i c l e s . No p r e c i p i t a t i o n o c c u r r e d d u r i n g r e c o v e r y p r i o r to r e c r y s t a l l i z a t i o n to a l t e r the r e c r y s t a l l i z a t i o n k i n e t i c s as h a s b e e n o b s e r v e d in a l u m i n u m k i l l e d s t e e l s . A n n e a l i n g s t u d i e s showed that the a d d i t i o n of t i t a n i u m a l t e r e d the r e c r y s t a l l i z a t i o n t e x t u r e in a m a n n e r h i g h l y f a v o r a b l e f o r e n h a n c e d d r a w a b i l i t y ( h i g h / ~ v a l u e s ) r e s u l t i n g f r o m an i n c r e a s e in the i n t e n s i t y of the {111} c o m p o n e n t . Heating r a t e and a n n e a l i n g t e m p e r a t u r e s w e r e found to e x e r t only a s m a l l i n f l u e n c e on the r e c r y s t a l l i z a t i o n t e x t u r e . The influence of t i t a n i u m on the r e c r y s t a l l i z a t i o n k i n e t i c s and g r a i n m o r p h o l o g y is d i s c u s s e d in t e r m s of i m p r o v e d p r o p e r t i e s c o m p a r e d to r i m m e d and a l u m i n u m k i l l e d s t e e l .
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recent years, considerable effort has been exp e n d e d on the e x a m i n a t i o n of the r e c r y s t a l l i z a t i o n b e h a v i o r of l o w - c a r b o n s t e e l and the influence of a l l o y i n g e l e m e n t s on t h i s b e h a v i o r . 1'2 This i n t e r e s t has b e e n both a c a d e m i c and p r a c t i c a l , f o r even in the a r e a of commercial low-carbon steel, where vast tonnages are p r o d u c e d , the annealing p r o c e s s is not c o m p l e t e l y u n d e r s t o o d . With l o w - c a r b o n s t e e l , one of the m a i n p r a c t i c a l i n t e r e s t s l i e s in i m p r o v e d d r a w a b i l i t y which in t u r n is s t r o n g l y a f f e c t e d b y the p r e f e r r e d c r y s t a l l o g r a p h i c t e x t u r e of the s h e e t . 3'4 F o r a s p e c i f i c m a t e r i a l , the t e x t u r e d e v e l o p e d upon r e c r y s t a l l i z a t i o n d e p e n d s p r i m a r i l y on the t y p e of d e f o r m a t i o n t e
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