Recent Results on the Brittle Fracture of Terfenol-D Specimens under Magnetic Field

Abstract

The following investigation has the purpose of describing, both experimentally and numerically, the fracture behavior of a giant magnetostrictive alloy commercially known as Terfenol-D. Single-edge precracked specimens have been analyzed via three-point bending tests, measuring fracture loads in the presence and absence of a magnetic field at various loading rates. The Strain Energy Density (SED), averaged in a finite control volume, has recently proved to be an excellent method of predicting brittle failures of cracked, U- and V-notched specimens made out of different materials. The effects of the magnetic field and of the loading rate on Terfenol-D failures have been studied, as well as discussing the ability of SED criterion to seize these effects, by performing coupled-field finite element analyses. Finally, a relationship between the size of the SED's control volume and the loading rate has been proposed and failures have then been estimated in terms of averaged SED.