The principal reasons which induced the authors to write this book and the features of the book are set forth in the preface to the Russian edition. That section of the science of metals which in Russian is called "metallovedenie" or the "physical chemistry of metals" is generally referred to in scientific and technical literature published in the English language by the term "physical metallurgy." These concepts are much broader than the term" metallography," used in the scientific and technical literature of various countries, and applied solely to research on the interrelationships of the structure and proper­ ties of metals and alloys. Each science must have its own subject and its own method of research. Certainly, all specialists will agree that metals and alloys, including their solid solutions, mechanical mix­ tures, and metallic compounds, form the subject of "physical metallurgy" or "physical chemis­ try of metals." The aim of this science. is to produce a theory and to elucidate the experimental relationships which ought finally to make it possible to calculate quantitatively alloys Of given properties for any working conditions and parameters.