Tin was known and used by ancient civilisations. Tin is a silvery white metal which is soft and pliable, and which emits the characteristic sound of "tin cry" when bent. It is a relatively common element, its abundance being 2.2 ppm in the earth's crust. Its principal ore is cassiterite, SnO₂, from which the metal is obtained by reduction. Tin forms a stable oxide coating on its surface which makes it unreactive in water; however, it is soluble in both acids and alkalis, and reacts readily with halogens. As tin has good chemical resistance, it is used as a coating of other metals to prevent corrosion, the coating of steel to produce tin plate being an important example of this application. Tin is widely used in the manufacture of soft solders where it is alloyed with other elements to produce a wide range of alloys with different characteristics. Tin is also a constituent of bronzes, pewter, certain bearing materials and fusible alloys.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.