Correlation of Structure Characteristics and Resonant Frequency Measurements with the Engineering Properties of Gray Iron

An investigation was conducted to learn more about the interrelations between the various physical and mechanical properties of gray iron. Particular emphasis was placed on exploring the factors which control the fatigue properties of gray iron. Four basic strength parameters -- density, hardness, dynamic elastic modulus, and damping capacity --were evaluated and correlated with tensile strength and mean fatigue limit.

The dynamic elastic modulus and damping capacity were determined from conventional resonant frequency equipment. Several quantitative relations were developed which permit estimation of the tensile strength and fatigue limit of gray iron without knowledge of the specific chemistry or solidification rate.