الفهرس 
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Abstract
Alloys are metallic materials consisting of two or more elements combined in such a way that they cannot be readily separated by physical means. More than 90% of metals used are in the form of alloys. Alloys can be divided into two types: ferrous and non- ferrous. In metallurgy, a non-ferrous metal is any metal that is not ferrous, including alloys, that does not contain iron in appreciable amounts. Groups of inorganic glassy materials which always contain one or more of the chalcogen elements S, Se or Te, in conjunction with more electropositive elements as As, Sb and Bi, are recognized as chalcogenide glasses but Ferroalloy refers to various alloys of iron with a high proportion of one or more other elements, for example ferrotitanium alloy.
Chalcogenide glasses are generally less robust, more weakly bonded materials than oxide glasses. Glasses were prepared from Ge, Se, As and Te elements with purity 99.999%.These glasses are reactive at high temperature with oxygen. Therefore, synthesis was accomplished in evacuated clean silica tubes. The tubes were washed by distilled water, and then dried in a furnace whose temperature was about 100C.
The weighted materials were introduced into the cleaned silica tubes and then evacuated to about 10-4 torr and sealed. The sealed tubes were placed inside the furnace and the temperature of the furnace was raised gradually up to 900C within 1 hour and kept constant for 10 hours. Moreover, shaking of the constituent materials inside the tube in the furnace was necessary for realizing the homogeneity of the composition. After synthesis, the tube was quenched into ice water. The glassy ingots could be
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obtained by drastic quenching. Then materials were removed from the tubes and kept in dry atmosphere. Thin films of the selected compositions were prepared by thermal evaporation technique under vacuum 10-4 torr with constant thickness 100 nm.