Solid solutions term is generally used for single phase alloys of metals. For metals, there are two mechanisms of solid solution; substitutional solid solutions and interstitial solid solutions. In this article we will explain the these solid solution mechanisms in a most basic terms.
In substitutional solid solutions, the average size of solvent and dissolved material atoms must be roughly the same. Because in this mechanism, there is a replacement of solvent atoms with dissolved atoms as shown by illustration (a) above. One of the biggest example for this kind of solivent mechanism is Brass in which zinc is dissolved into the copper. For substitutional solid solutions, lattice types must be same and the valences of solvent and dissolvents must be different. In generali the lower valence is more likely to be solvent.
In interstitial solid solutions, the dissolved atoms takes the blank locations between solvent atoms. So the sizes of solvent atoms must very high compared with dissolved atoms. These small dissolved atoms fit into the blanks between the bigger solvent atoms as shown by the illustration (b) above. One of the biggest example for this kind of solid solution is Iron-Carbon solid solutions. In Iron-Carbon solutions, solvent is iron and the dissolved atoms are carbon atoms. Carbon atoms are mush more smaller compared with Iron atoms.
But in general, the new alloy structure will be much more superior in terms of mechanical charactristics.
The explanation of Substitutional solid solutions and Interstitial solid solutions can be explained like above briefly. If you have any comments or questions about ‘Substitutional solid solutions and Interstitial solid solutions’, do not forget to leave them below!
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