OVERVIEW

All engineering products are made of materials. Thus, engineers become directly involved with materials, whether they be design engineers, production engineers, or applications engineers. Their familiarity with a wide spectrum of materials becomes particularly important as they advance through management and into administration, where they must oversee the activities of additional engineers on their technical staffs.

The way that an engineering product performs in service is a consequence of the combination of the components of that product. Thus, a cellular phone must have the diodes, resistors, capacitors, etc., that function together to meet its design requirements. Likewise, a competitively produced car must possess a carefully designed engine with its numerous parts, as well as safety features and operating characteristics that meet customer approval. Materials are pertinent to each and every design consideration.

Just as it is to be expected that the internal circuitry of a four-function hand calculator will differ from the internal circuitry of its multifunctional scientific counterpart, the internal structure of a steel gear must differ from that of the sheet steel to be used in an automotive fender. Their roles, and therefore their properties, are designed to be different.

The variations in the internal structures of materials that lead to property differences include variations in atomic coordination and electronic energies, differences in internal geometries (microstructures), and the incorporation of larger structures, sometimes called macrostructures. Each of these is considered in the following sections, along with procedures for obtaining desired structures and properties.