Stress Dependency on Ultrasonic Wave Propagation Velocity. II. Third Order Elastic Constants of Steels

The theory of wave propagation in a stressed solid was applied to the measurement of ultrasonic wave propagating velocity through tensile specimens of carbon steels containing 0.2-0.5% C, and Murnaghan's third order elastic constants of both Eulerian and Lagrangian formulation were obtained for those steels. They were ten times as large as the second order elastic constants, and values of the Eulerian constant n in them largely changed with composition of specimens. It was found that there was a simple relation between the Eulerian and Lagrangian third order elastic constants. 22 ref.--AA