What are the properties of alloys? [closed]

You spend a lot of time in chemistry talking about molecular amd ionic compounds, but I'm interested in what you can do with metals only. What is the difference between the properties (physical & chemical) of pure metals and those of alloys? Is it possible to predict the properties of alloys before making them? Can you make alloys with mercury?

closed as too broad by M.A.R., Loong♦, Klaus-Dieter Warzecha, Ben Norris, Jon CusterMar 24 '16 at 1:42

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For example, steel has very different mechanical properties from pure iron. There are about a bazillion different kinds of steel, each with different impurities mixed in to give specific mechanical properties, optimizing strength, fatigue life, corrosion resistance, etc. Much of the development has been through insight gained by experience. More recently, the CALPHAD approach is giving more fundamental insight through thermodynamic modeling, but predicting the mechanical properties $\it a\ priori$ is still difficult to impossible.