The escalating cost of material testing in terms of money and time for critical components in some industry fields such as aerospace, transportation, and military increases the need for a an effective, fast, and cheap testing method that can efficiently estimate the structure s mechanical properties. This book introduces the use of modal analysis in a novel approach towards the identification of mechanical properties for metallic components. Modal analysis has been known as an efficient technique in predicting the dynamic parameters of metal structures. In this book, an extensive investigation to find a relationship between the mechanical properties and dynamic parameters of metallic elements is described. Part of the book is devoted to predicting the effects of heat treatment of steel and ductile cast iron by the means of dynamic testing. A simple application of labVIEW programming software for the automation of the identification process is described.