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CtCyt Alloys | Introduction. [ Metals are insoluble in ordinary solvents such as. water, alcohol, ether etc. But one metal can be dissolved in another metal in molten state forming a homogeneous quid mixture, This mixture on solidification is called as an Alloy. Most of the metals in fused state are miscible in all proportions to form alloys, For example, lead and tin mix up in all proportions and thus form an alloy. But some fused metals are not miscible with each other to form a homogeneous mixture and therefore, they do not form alloys. For example, zinc and lead are not miscible with one another and hence no alloy of zinc and lead is formed. Not only the metals can form the alloys with each other, but non-metals can also form the alloys with metals in the similar way. Non-metals like silicon, phosphorus, boron, sulphur, carbon can form the alloys when mixed with metals. For example, pig iron and steel are alloys of iron and carbon. , | n Hence|the alloy may be called as a homogeneous mixture of two or more elements out of which one at least is essentially a meta Alloys containing mercury as one of the components are called amalgams. For example, sodium-amalgam, zinc-amalgam. It should be noted that the homogeneous mixture of the consti- tuents of the alloys, when in molten state, may or may not be homo geneous upon solidification. Hence an alloy may be either (7) homo geneous or (ii) hetrogeneous. Homogeneous alloys consist of a single phase of (a) a solid solution, (b) a pure chemical compound of (c) a solid solution of a compound in excess of one of the metal. For example, (i) an alloy of coinage silver is homogeneous. It con- sists of small crystal grains, each of which is a solid solution of coppe and silver, (ij) tantalum carbide, TaC, is a homogeneous alloy of tantalum which is a compound. : Heterogeneous alloys consist of a mixture of different phase which may be (a) pure metals, (6) one or more pure compounds, of (c) solution of metals or their compounds in metals. Nien for the preparation of alloys. aving meemnous: 8° 5 
