Abstract
The origin of this monograph lies in a simple fact: there is a paradigm with cast irons, namely that these alloys have been produced and cast for thousands of years, yet they are among the most complicated alloys if we consider the formation of their microstructure by solidification and transformations in the solid state. The positive side of this complexity is that it offers a wide range of possibilities for manipulating their microstructure. With the evolution of melting furnaces in the 19th century, the silicon content of cast irons increased, leading to the development of the silicon cast irons that are the subject of this monograph. The essential step, however, was the discovery in the middle of the 20th century that it is possible to change the shape of graphite by transforming the interconnected lamellae into discrete spheroids. In this way, cast iron became a material for safety parts and was no longer limited to construction. This historical development and the research effort during the first part of the 20th century have been described in reviews published in the 1960s. Since then, developments in metallographic analysis have led to a wealth of research aimed at describing and understanding graphite formation and the microstructure of cast irons during solidification and heat treatment. This monograph is not intended to be an exhaustive review of the literature of the last 50 years, but aims to propose a coherent vision of the formation of the microstructure of cast irons based on the work carried out jointly or in parallel by its authors. Current controversies are sometimes indicated but are not discussed in order to emphasize open questions. Finally, we should mention that our work has greatly benefited from the dynamism of the European Cast Iron group (ECI), an informal forum open to all (European academics and industrialists) for more than 15 years. It is in this same spirit of discussion that this monograph is freely available.