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304L s t a i n l e s s steel, f a b r i c a t e d by c o n v e n tional powder m e t a l l u r g y t e c h n i q u e s , has b e e n s u c c e s s f u l l y i n c o r p o r a t e d into f i l t r a t i o n d e v i c e s . T y p i cally, t h e s e d e v i c e s r e q u i r e a c o m b i n a t i o n of p r o p e r t i e s such as pore size, p o r o s i t y , s t r e n g t h , p e r m e a b i l i t y and c o r r o s i o n r e s i s t a n c e . In spite of the w i d e s p r e a d use of 304L, the p r o c e s s i n g of p o r o u s s t r u c t u r e s f r o m this alloy is p o o r l y d o c u m e n t e d . To d e t e r m i n e the s i n t e r i n g k i n e t i c s that govern the f o r m a t i o n of p o r o u s 304L s t a i n l e s s s t e e l , the p r e s e n t study e x a m i n e d the s i n t e r i n g b e h a v i o r of an i r r e g u l a r l y shaped, subsieve ( - 4 4 ~tm) 304L s t a i n l e s s s t e e l p o w d e r . The study, which c o v e r e d a f r a c t i o n a l d e n s i t y r a n g e f r o m 0.58 to 0.87, showed that the powder s i n t e r s p r e d o m i n a n t l y by a v o l u m e diffusion m e c h a n i s m , with final d e n s i f i c a t i o n b e i n g i n f l u e n c e d by g r a i n growth. T h r o u g h an u n d e r s t a n d i n g of the s i n t e r i n g k i n e t i c s , the s h r i n k a g e , d e n s i t y , and pore c h a r a c t e r i s t i c s of the powder can be p r e d i c t e d . The p r e s e n t r e s u l t s a r e c o n s i d e r e d to be g e n e r a l l y r e p r e s e n t a t i v e of the p r o c e s s i n g of a u s t e n i t i c s t a i n l e s s s t e e l p o w d e r s .

h y d r o g e n a t m o s p h e r e s in a c o n s t a n t - l o a d , l o w - f o r c e d i l a t o m e t e r . S h r i n k a g e was m e a s u r e d by an a l u m i n a p u s h - r o d p l a c e d in contact with the s p e c i m e n . T o t a l s p e c i m e n p r e s s u r e due to the p u s h - r o d loading was 3 k P a . The p u s h - r o d was d i r e c t l y linked to a l i n e a r d i f f e r e n t i a l t r a n s f o r m e r whose output was a m p l i f i e d and r e c o r d e d both d i g i t a l l y and g r a p h i c a l l y , along with the t e m p e r a t u r e and t i m e . The output was c a l i b r a t e d to d i s p l a c e m e n t by m e a n s of a m i c r o m e t e r built into the s y s t e m . T e m p e r a t u r e was c o n t r o l l e d and m e a s u r e d with two P t / P t - 1 0 pct Rh t h e r m o c o u p l e s c a l i b r a t e d a g a i n s t the ot ~ 7 t r a n s f o r m a t i o n of pure i r o n . The e n t i r e s y s t e m was c a l i b r a t e d (i.e., t h e r m a l e x p a n s i o n effects, t e m p e r a t u r e p r o f i l e , and h e a t i n g rate) u s i n g solid 304L s t a i n l e s s s t e e l and t a n t a l u m s a m p l e s . A p r o g r a m m e d h e a t i n g r a t e of 20 K / m i n was used in a l l e x p e r i m e n t s , and the i n i t i a l cooling r a t e was i n e x c e s s of 100 K / m i n . I s o t h e r m a l conditions w e r e a u t o m a t i