ABSTRACT
This chapter uses many examples of metals when explaining and discussing features of materials' behaviour and structure. It extends some of these aspects which are of particular importance and relevance to metals, notably, ductility, plasticity and grain structure, and then shows how these lead to methods of strengthening and forming metals, subjects often collectively known as physical metallurgy. To gain an understanding of the mechanisms and controlling factors of plastic deformation (or the lack of it), the chapter considers the imperfections and impurities in the crystal lattice and, on a slightly larger scale, the grain structure. Alloys are inevitable results of production but are deliberately introduced to enhance some desirable properties, particularly strength. Dislocations occur when the atoms do not arrange themselves in a perfect regular repeating pattern when the metal solidifies from the melt. The movement of the dislocation results in a shear displacement along a slip plane.
