Stress Corrosion Damage Detection in Bolts by Stress Wave Attenuation

摘要

Preliminary work has shown that damage in a short round bar can be quantified by determining the attenuation of a propagating stress wave. A bar provides a waveguide for the stress wave to travel and has a simple geometry. A shoulder or other geometric feature will reflect the excitation, which would change the recorded response. To extend this work, piezoelectric patches were attached to bolts, which were then exposed to a hostile environment and stress corrosion crack growth was allowed to take place in the material. Immediately after exposure, these bolts were pulled to failure in a tensile test machine, to determine their residual strength. A relationship between the signal attenuation and residual strength was obtained.