Machining process - Presentation

Although they are not very economical in terms of raw materials and energy, and therefore face strong competition from other material shaping processes, the various machining processes remain indispensable for the production of many parts. It should also be noted that the performance of these processes has been greatly enhanced by the development of non-traditional machining processes after the Second World War, for machining materials that do not lend themselves well to traditional processes, and by the productivity gains achieved with the advent of numerically-controlled machine tools for automatic part production, the practice of high machining speeds, and the development of new tool materials that are more resistant to the high temperatures induced by high cutting speeds. This article introduces the entire "machining" section. The implementation of machining operations to produce a part or a family of parts is a complex problem, due to the multiplicity of processes available and the wide variety of part specifications and constituent material properties. This article aims to provide the reader with the fundamentals of the problem and, as such, has a threefold objective:

• define the machining operation, situate its economic importance in relation to other material shaping processes (shaping, sintering, molding) and specify the main characteristics of a machining operation;

• present the specific features of each of the major classes of machining processes: cutting, abrasive machining and physicochemical machining (all non-traditional processes);

• compare the performance of these different processes from various practical points of view: applicability to different materials, material throughput, power requirements and energy efficiency, possible machining operations, final properties of the part, economic aspects of their implementation.

Readers will be referred to more specialized articles for more detailed information, or even to specialized books. Finally, we'll look at how these processes are likely to evolve over the next few years.