Mechanical Properties of Metals and Their Cavitation-Damage Resistance

Abstract

Detailed investigations with a magnetostriction apparatus were carried out to determine the cavitation-damage resistance of eleven metals in distilled water at 80 F. The cavitation-damage resistance is defined as the reciprocal of the rate of volume loss for a given metal. Among the mechanical properties investigated (ultimate tensile strength, yield strength, ultimate elongation, Brinell hardness, modulus of elasticity and strain energy) the most significant property which characterizes the energy-absorbing capacity of the metals, under the repeated, indenting loads due to the energy of cavitation bubble collapse in the steady-state zone, was found to be the fracture strain energy of the metals. The strain energy is defined as the area of the stress-strain diagram up to fracture. The correlation between the strain energy and the reciprocal of the rate of volume loss leads directly to the estimation of the intensity of cavitation damage; this intensity varies as the square of the displacement amplitude of the specimen. All these conclusions are limited to the steady-state zone of damage.