Effect of manganese on the annealing texture and strain ratio of low-carbon steels
- PDF / 1,362,852 Bytes
- 8 Pages / 612 x 792 pts (letter) Page_size
- 72 Downloads / 217 Views
V A R I O U S a u t h o r s ~-4 have shown that the p l a s t i c s t r a i n r a t i o (i.e. the r a t i o of s t r a i n in the width d i m e n s i o n to s t r a i n in the t h i c k n e s s d i m e n s i o n in a s i m p l e t e n s i o n test) o r r value of low-carbon~ sheet s t e e l s c a n be i m p r o v e d s u b s t a n t i a l l y by d e c a r b u r i z a t i o n d u r i n g r e c r y s t a l l i z a t i o n a n n e a l s . This i m p r o v e m e n t is a c o n s e q u e n c e of g r a i n growth d u r i n g d e c a r b u r i z a t i o n , which r e s u l t s in a s h a r p e n i n g of the texture.4 D u r i n g the past s e v e r a l y e a r s , a s e r i e s of i n v e s t i g a t i o n s have b e e n conducted at o u r l a b o r a t o r y on the v a r i o u s f a c t o r s that m a y i n f l u e n c e t e x t u r e f o r m a t i o n d u r i n g such d e c a r b u r i z a t i o n a n n e a l s . 5-6 In a l l t h e s e i n v e s t i g a t i o n s , t e x t u r e d e v e l o p m e n t in c o m m e r c i a l l o w - c a r b o n s t e e l s and i n l a b o r a t o r y v a c u u m - h e a t s of a l o w - c a r b o n i r o n alloy was s t u died s i m u l t a n e o u s l y . It was n o t i c e d that although a n i m p r o v e m e n t of the r v a l u e s of the c o m m e r c i a l s t e e l s was a l w a y s a c c o m p a n i e d by g r a i n c o a r s e n i n g , high r v a l u e s w e r e o b t a i n e d in the " p u r e " F e - C alloy with v e r y l i m i t e d g r a i n growth following r e c r y s t a l l i z a t i o n . In o t h e r w o r d s , a good d r a w i n g - q u a l i t y t e x t u r e was o b t a i n a b l e in the " p u r e " F e - C a l l o y by p r i m a r y r e c r y s t a l t i z a t i o n , w h e r e a s s u b s e q u e n t g r a i n c o a r s e n i n g was n e c e s s a r y to i m p r o v e the t e x t u r e of c o m m e r c i a l s t e e l s . This o b s e r v a t i o n suggested the p o s s i b i l i t y that the n o m inal c o n t e n t of m a n g a n e s e o r s i l i c o n in the c o m m e r c i a l s t e e l s might have b e e n r e s p o n s i b l e for the f o r m a t i o n of the i n f e r i o r r e c r y s t a l l i z a t i o n t e x t u r e s . The p r e s e n t i n v e s t i g a t i o n was u n d e r t a k e n to e x p l o r e this p o s s i b i l i t y , and to d e t e r m i n e the effective c o n c e n t r a t i o n l i m i t s . THE
TEXTURAL
BEHAVIOR O F AN Fe-C-Si A L L O Y
To establish first whether manganese or silicon was mainly responsible for the difference in behavior between the "pure" Fe-C alloy and the commercial steels, a laboratory vacuum-melted Fe-C-Si alloy was studied in conjunction with a continuously-cast c o m mercial low-carbon steel. The carbon, silicon, and other residual impurity contents of the alloy were c o m parable to those of the steel; the main difference in composition between the two was in their manganese HSUN HU and S. R. GOODMANare with the E. C. Bain Laboratory for Fundamental Research, U.S. Steel Corp., Research Center, Monroev
Data Loading...
