It would be impertinent for the writer, who is after all a materials technologist and not a designer, to attempt to specify, even in general terms, the whole range of skills which a successful designer needs to employ in his profession. However, the hypothesis is still held that a designer is likely to focus his skills primarily upon the mechanical, aesthetic and functional requirements of products, and would not be expected to possess a general knowledge of all other aspects of the design process which would be available to him in a perfect world. When arriving at design decisions, experience makes a vital contribution, as it must seldom be possible to analyse in depth all aspects of an engineering problem by reducing every parameter to a numerical value. In our real world these decisions must be supported by an intuitive feel for their consequences, being in many cases arrived at from inadequate supporting data.

The following sections emphasise those aspects of the designer's work which are closely linked to the process of materials selection. The cataloguing of unfamiliar topics throughout this chapter should remind the reader of his need for expert advice from time to time; here, as in the rest of the book, the content of this chapter is designed to make the reader sufficiently familiar with the materials aspects of his problem that he can formulate questions properly and have some hope of understanding the expert's response.