ABSTRACT
A great variety of materials has been produced, and more are being produced in seemingly endless diversi cation. Material may be crystalline or noncrystalline. A crystalline material is made up of a number of small units called crystals or grains. Most materials must be processed before they are usable. Table 2.1 gives a general classi cation of engineering materials. This book is concerned with the macroscopic structural behavior: properties are based on experiments using samples of materials of appreciable size. It is clear that a macroscopic structure includes a number of elementary particles forming a continuous and homogeneous structure held together by internal forces. The website at www.matweb.com offers extensive information on materials.
