Ferromagnetic Functional Materials

This chapter aims to give a brief summary about functional ferromagnetic materials. Firstly, a concise historical development of magnetism is given, which is followed by a brief revision of a few technical terms necessary to bring out the understanding of the phenomenon of magnetism and its underlying science. It describes the magnetism from the atomic-scale to bulk scale. Furthermore, the soft magnetic and hard magnetic materials are discussed and the methods of enhancement of their magnetic properties have been highlighted. Crucial magnetic properties of these functional materials depend strongly on microstructure. An emphasis has been given towards the understanding of materials selection, phase stability and microstructural changes in designing of functional magnetic materials. Also, this chapter is to familiarize the readers about the historical development and current topic of interest in the field of soft and permanent magnetic materials, but it will not cover these subjects exhaustively. It also looks at their challenges, potentials as well as the future prospects. At the end, low dimensional and molecular magnets have been briefly discussed.