Essential Manufacturing

17Material and Process Selection

The importance of an integrated approach to all aspects of manufacturing is emphasised here at the process selection stage. To select an appropriate process for a product, due consideration must be given to the material used. Conversely, the design engineer when considering the material for his product must also consider the processes that will be used to form the product. We will therefore, at this interface between product design and product manufacture, briefly consider material selection as well as process selection.

Figure 17.1 shows the factors to be considered when carrying out the material selection and process selection activities; it also indicates their close interrelationship. When selecting a material for a product the designer will try to juggle the material attributes shown in Figure 17.1 to achieve an optimum solution. For example, the material will require specific mechanical properties, it will need to possess certain minimum shear, compressive and tensile strengths, or it may have to exhibit high elasticity, toughness or wear resistance. Physical properties may also be important, for example, thermal and electrical conductivity, optical characteristics or magnetic properties. The designer's choice of material will also be influenced by the expected lifetime of the product, the implications of product failure and the type of environments in which the product will be used. The ‘manufacturability’ of the material is obviously ...