The Mechanical Behaviour of Engineering Materials aims to relate properties and structure, and to provide a theoretical basis upon which to extrapolate when conditions or materials outside previous experience arise. The present text refers primarily to metals and alloys, other (non-crystalline) solids are treated rather less fully. This is largely dictated by the state of knowledge at the present time, for although there is a large mass of data concerning the properties of non-metallic materials, much of this is empirical and a full explanation is made difficult by the complexities of an irregular initial structure. The book can be divided into the three sections covering constitution, properties, and significance of test data. Separate chapters discuss properties such as heterogeneity, elasticity, plasticity, and fracture. Subsequent chapters deal with tensile and hardness tests; creep, fatigue and impact tests; and the selection of engineering materials. Throughout the text the author has endeavored to confine the discussion to those aspects of materials science which appear to be reasonably well understood at the present time.