Rapid testing method for interface crack analysis of an adhesive bonded joint using an electrodynamic shaker

Abstract

An electrodynamic shaker is used to reduce the testing time and the costs of the mechanical lifetime testing of an adhesively bonded sample. By exploiting the characteristics of the Eigen frequencies of a purposely designed sample, a crack propagates in a controlled manner under the cyclic loading: as the crack propagates, the Eigen frequency departs from the excitation frequency and the load decreases. The excitation of samples under the Eigen frequency is a method currently used for metals to accelerate the results output for high cycle fatigue [1] and has been successfully employed to initiate and propagate cracks in a stable manner by George et al. [2] moreover, they decreased the testing time from 4.6 hours to 11 minutes for 106 cycles.