2. Fundamentals of materials science
4 In materials science, rather than haphazardly looking for and discovering materials and exploiting their properties, the aim is instead to understand materials so that new materials with the desired properties can be created. 5 Thebasis of materials science involves relating the desired properties and relative performance of a material in a certain application to the structure of the atoms and phases in that material through characterization. The major determinants of the structure of a material and thus of its properties are its constituent chemical elements and the way in which it has been processed into its final form. These characteristics, taken together and related through the laws of thermodynamics, govern a material s microstructure, and thus its properties.
6 The manufacture of a perfect crystal of a material is currently physically impossible. Instead materials scientists manipulate the defects in crystalline materials such as precipitates, grain boundaries （Hall-Petch relationship）, interstitial atoms, vacancies or substitutional atoms, to create materials with the desired properties.
7 Not all materials have a regular crystal structure. Glasses, some ceramics, and many natural materials are amorphous, not possessing any long-range order in their atomic arrangements. Polymers display varying degrees of crystallinity, and many are completely non-crystalline. Polymers are studied in the fields of polymer chemistry, polymer physics, and polymer science.
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