Material Selection and Process Mapping
The selection of suitable materials is an important function of an engineer or designer to satisfy specific design, production, operational and maintenance requirements and in doing this, produce a component or assembly at an acceptable cost. There are thousands of different materials available to the engineer and the range of mechanical and physical properties possible is extremely wide. However, the selection of material cannot be carried out in isolation to fit into a design requirement. It must involve consideration of design and manufacturing factors. There is a complex inter-dependence among the three elements of design, material and manufacture.
Figure 1
This unit illustrates how material properties and other factors should be used in selecting a material for given the design situation. Selection of materials is now easier and faster, because of the availability of computerized and extensive databases, which provide much greater accessibility to information than previously available. However, to facilitate the selection of materials and the determination of the parameters described later in this unit, expert-system software (smart databases) is now available. With proper input of product design and functional requirements, this would identify an appropriate material for a particular application.
The following considerations are important in materials selection for products :
1. Do the materials selected have properties that unnecessarily exceed minimum requirements and specifications?
2. Can some materials be replaced by others that are less expensive?
3. Do the materials selected have the appropriate manufacturing characteristics?
4. Are the raw materials (stock) to be ordered for a specific use available in standard shapes, dimensions, tolerances, and surface finishes?
5. Is the material supply reliable?
6. Are there likely to be significant price fluctuations or increases for the materials in near future?
7. Can the materials be attained in the required quantities within the desired time frame?
Objectives
After studying this unit, you should be able to
- Know the general type of materials utilized in manufacturing industry,
- Understand the role of the material selection in the design process,
- Elaborate the factors influencing the material selection, and
- Know the importance of selection of right manufacturing process.