Mössbauer study of internally oxidized silver-tin alloys

• Autores: Sánchez, Francisco Homero; Mercader, Roberto Carlos; Pasquevich, Alberto Felipe; Bibiloni, Aníbal Guillermo; López García, Alberto Raúl
• Año de publicación: 1984
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: Química
• Institución: Universidad Nacional de La Plata

A Mössbauer study of internally formed oxides as a function of oxidation temperatures between 200 ℃ and 850 ℃ was performed on previously annealed 1 at%AgSn alloys. The oxide formed at high temperatures (t ⩾ 500 ℃) consists in agglomerates of tin dioxideδCaSnO3/RT = 0.00 ± 0.01 mm/s, δQ=0.50 ± 0.03 mm/s). The low temperature oxide (t ⩽ 300 ℃) is characterized byδCaSnO3/RT = 0.29 ± 0.02 mm/s and δQ=0.32 ± 0.03 mm/s, and could be in the form of one-Sn-atom oxide complexes in the silver matrix. From the measured isomer shifts in the range 400 ⩽t ⩽ 550 ℃, the maximum contribution of the silver matrix to the effective number of electrons per Sn atom in oxide agglomerates has been estimated ℴ have a value of about 0.06. The effect of the cold work on the hyperfine parameters of the oxidized tin has also been investigated. ‘As rolled ’ samples were found to attain the same values of isomer shifts and quadrupole splittings as annealed specimens, but at lower temperatures.
Facultad de Ciencias Exactas