Electrical conductivity measurements on the Liquid PbO-PbCI 2 -PbS system
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1. D. Belitskus:Z Metals, 1973,vol. 25, pp. 39-44. 2. O. K. Mehra, D. K. Bose,and C. K. Gupta: Trans. IIM, April, 1973, pp. 1-7. 3. O. K. Mehra,D. K. Bose,and C. K. Gupta: Met. Trans., 1974,vol. 4, pp. 69194. 4. B. SmithHopkins: Vanadium, chapt. 14, StripesPublishingCo., Champaign, I11., 1940, 24 pp. 5. Georgevan Arsdale:Hydrometallurgy of Base Metals, pp. 26-28, McGraw-Hill Book Co., Inc., NewYork, 1953. 6. C. J. Chindgren, L. C. Bauerle,and J. B. Rosenbaum: U.S. Bur. MinesReport, Inv. No. 5973, 1962. 7. C. J. Chindgren, L. C. Bauerle,and B. K. Shibler: U.S. Bur. MinesRept., Inv. No. 7058, 1967. 8. K. U. Nair, T. K. Mukherjee,and C. K. Gupta: J. Less-Common Metals, 1975, vol. 41, pp. 87-95. 9. T. K. Muldaerjeeand C. K. Gupta: J. Less-Common Metals, 1972,vol.27, pp. 251-54.
Electrical Conductivity Measurements on the Liquid PbO-PbCl2-PbS System K. NAGATA, H. SUGAWARA, AND K. S. GOTO A l l o y s f o r high t e m p e r a t u r e u s e s a r e u s u a l l y c o v e r e d by a p r o t e c t i v e oxide l a y e r which has a high m e l t i n g point. H o w e v e r , this l a y e r would d i s s o l v e , if it w e r e c o n t a c t e d by a liquid m i x t u r e with low m e l t i n g point such as, f o r e x a m p l e , P b O - P b C l z - P b S m i x t u r e . l The r a t e of the d i s s o l u t i o n would be v e r y l i k e l y c o n t r o l l e d by the diffusion of ions in the liquid p h a s e . B e c a u s e the ionic d i f f u s i v i t y is r e l a t e d to the e l e c t r i c a l c o n d u c t i v i t y due to ions, c o n d u c t i v i t y m e a s u r e m e n t s should be v e r y helpful in d e v e l o p i n g a b e t t e r u n d e r s t a n d i n g of the m e c h a n i s m of hot c o r r o s i o n of a l l o y s by fused s a l t s . When the m i c r o m e c h a n i s m of the t r a n s p o r t of ions is s i m i l a r f o r e l e c t r i c a l conduction and t r a c e r d i f fusion, the d i f f u s i v i t y can be e s t i m a t e d f r o m the c o n d u c t i v i t y with the help of the N e r n s t - E i n s t e i n r e l a t i o n ; kTtif D ~ r = ni ( z i e) 2 (r
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R e c e n t l y , Goto, S a s a b e and K a w a k a m i z h a v e e x t e n s i v e l y e x a m i n e d the v a l i d i t y of t h i s e q u a t i o n on s e v e r a l liquid o x i d e s y s t e m s of m u l t i c o m p o n e n t s , u s i n g the d a t a of c o n d u c t i v i t y and d i f f u s i v i t y in l i t e r a t u r e s . Th e r e s u l t i n d i c a t e s that the d i f f u s i v i t y can be a p p r o x i m a t e l y e s t i m a t e d f r o m the c o n d u c t i v i t y and the s p e c i f i c d e n s i t y but with the c o r r e c t i o n f a c t o r of about 0.5, which is the a v e r a g e of the c o r r e c t i o n f a c t o r s f o r v a r i o u s oxide s y s t e m s . In the p r e s e n t s y s t e m , the c h a r g e c a r r i e r s would be p r e d o m i n a n t l y Pb z* and thus the t r a c e r d i f f u s i v i t y of l e a d in the m e l t could be e s t i m a t e d f r o m the c o n d u c t i v i t y m e a s u r
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