On the gibbs energy interaction parameters of oxygen and nitrogen in liquid alloys
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h l a r g e n u m b e r of t h e o r e t i c a l p a p e r s h a s b e e n p u b l i s h e d on the t h e r m o d y n a m i c p r o p e r t i e s of dilute liquid s o l u t i o n s . 1-1e One of the m o d e l s was p r o p o s e d b y W a g n e r to d e s c r i b e the effect of a l l o y i n g e l e m e n t s on the a c t i v i t y c o e f f i c i e n t of a n o n m e t a l l i c s o l u t e in b i n a r y liquid a l l o y s w h e r e the c o n c e n t r a t i o n of the s o l u t e i s low. T h i s m o d e l c o n s i s t s of one a d j u s t a b l e p a r a m e t e r h and is e q u i v a l e n t to the c e n t r a l a t o m m o d e l . ~4-Ie T h i s value of h m a y be p r e d i c t e d f r o m the c o r r e l a t i o n of Chiang and Chang l~ b a s e d on the d a t a of oxygen in b i n a r y liquid a l l o y s . T h i s c o r r e l a t i o n was a l s o found to be v a l i d by L i n and Chang ~~ f o r n i t r o g e n in b i n a r y liquid a l l o y s . In the a n a l y s i s of the t h e r m o d y n a m i c d a t a of o x y g e n in b i n a r y liquid a l l o y s , Chiang and Chang ~~ found t h a t the o n e - p a r a m e t e r m o d e l is not c a p a b l e of q u a n t i t a t i v e l y d e s c r i b i n g the effect of a l l o y i n g e l e m e n t s on the a c t i v i t y c o e f f i c i e n t of oxygen in many b i n a r y a l l o y s . A c c o r d i n g l y , u s i n g the a p p r o a c h of W a g n e r , 9 they had e x t e n d e d the W a g n e r m o d e l to have two e n e r g y p a r a m e t e r s h~ and he. T h e two p a r a m e t e r m o d e l is c a p a b l e of q u a n t i t a t i v e l y d e s c r i b i n g the v a r i a t i o n of the a c t i v i t y c o e f f i c i e n t of oxygen with a l l o y c o m p o s i t i o n . S u b s e quently, two c o r r e l a t i o n s , which p r e d i c t the v a l u e s of hi and he, w e r e p r e s e n t e d by Kuo and Chang e~ b a s e d on the d a t a of oxygen in s e v e r a l b i n a r y liquid a l l o y s . U s ing the a b o v e - m e n t i o n e d a p p r o a c h , it i s p o s s i b l e to p r e d i c t the Gibbs e n e r g y i n t e r a c t i o n p a r a m e t e r s of oxygen and n i t r o g e n in liquid m e t a l s if the v a l u e s of the a c t i v i t y c o e f f i c i e n t s of the n o n m e t a l l i c s o l u t e s in the two p u r e m e t a l components and t h o s e of the t h e r m o d y n a m i c p r o p e r t i e s of the b i n a r y m e t a l a l l o y s a r e known. The o b j e c t i v e s of the p r e s e n t p a p e r a r e 1) to t e s t the v a l i d i t y of this a p p r o a c h u s i n g the l a r g e n u m b e r of e x p e r i m e n t a l d a t a a v a i l a b l e in the l i t e r a t u r e on the Gibbs e n e r g y i n t e r a c t i o n p a r a m e t e r s , 2) to c o m p a r e the p r e s e n t a p p r o a c h with those a v a i l a b l e in the l i t e r a t u r e , and 3) to p r o v i d e b a s i c data, both e x p e r i m e n t a l l y d e t e r m i n e d and e s t i m a t e d v a l u e s , f o r p r e d i c t i n g the Gibbs e n e
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