Industrial applications of metallurgical studies
The behavior of metals and alloys under stress is important in connection with the forging of metal components. In this process the hot or cold metal is squeezed or hammered into shape instead of being cast in a mould (Fig. 13.11 and 13.12). Fig. 13.13 shows the crystal grain flow which takes place during a forging operation. In this condition the material becomes much tougher and more resistant to the formation of cracks which would lead to ultimate fracture. Examination of the crystal structure and behavior of materials has led to the development of tough alloys so vital to human safety as, for example, in aircraft construction.