Silver was known to ancient civilisations. Silver is a soft, malleable metal with a characteristic sheen. It has the highest thermal and electrical conductivities of all metals. It is generally found uncombined, or in the sulphide or arsenide ores from which it can be recovered as a cyanide complex which is subsequently reduced to the metal, in aqueous solution, by the use of zinc. The pure metal is stable to water and oxygen but is attacked in air by sulphur bearing compounds to form the characteristic black layer of silver sulphide. It is soluble in sulphuric and nitric acids. Some silver salts are sensitive to light (e.g. AgI, AgCl and AgBr) and are of fundamental importance to photography. Other applications and industries in which silver is used include the manufacture of jewellery (both as the pure metal and as a constituent of various alloys), the electrical industry (e.g. in the manufacture of contacts) and for the silvering of glass.
Polvere - Piccole particelle con un'intervallo di dimensioni definito. I materiali descritti come precursori delle leghe non sono leghe vere e proprie, ma sono ottenuti sinterizzando un mix di polveri dei metalli componenti per ottenere la lega per diffusione. La torta risultante è affinata e setacciata per ottenere l'intervallo delle dimensioni delle particelle richiesto. Se non diversamente specificato, le dimensioni della particella mostrata sono solo per guida. Non forniamo alcuna garanzia sulla distribuzione delle dimensioni delle particelle, tra le dimensioni minime e massime quotate o una forma delle particelle specifica.
