TABLE OF CONTENTS 
A 1000 tonne forging press. (Image courtesy of the Fu Sheng Group, Sporting Goods Division.)
Materials and processing are inseparable. Ores, minerals and oil are processed to create the stuff of engineering in clean, usable form. These are shaped into components, finished and joined to make products. Chapter 3 defined a hierarchy for these processes; in this chapter we explore their technical capabilities and methods for choosing which to use. Increasingly, legislation and public opinion require that materials are recycled at the end of product life. New processes are emerging to extract usable material from what used to be regarded as waste.
The strategy for choosing a process parallels that for materials: screen out those that cannot do the job, rank those that can (usually seeking those with the lowest cost) and explore the documented knowledge of the top-ranked candidates. Many technical characteristics of a process can be described by numeric and non-numeric data: the size of part it can produce, the surface finish of which it is capable and, critically, the material families or classes it can handle and the shapes it can make. Constraints on these provide the inputs for screening, giving a short list of processes that meet the requirements of the design.
There is another aspect to this. It relates to the influence of processing on the properties of the materials themselves. Materials, of course, have properties before they are shaped, joined or finished and processing is used to...
