ICE METAL INTERFACES - FRACTURE ENERGY AND FRACTOGRAPHY/

Results are presented of the fracture tests of ice/metal interfaces in an attempt to utilize fracture mechanics to characterize the failure of ice/solid adhesion. The four-point bending delamination specimen wa s used to measure the fracture energy of ice/aluminium and ice/steel j oints at -15 degrees C. The interfacial fracture energy was found to b e dependent on ice type and formation procedure of the ice/metal compo sites. Crack growth was in a manner of asymmetrical bursting, and both cohesive and adhesive failure mechanisms were observed. Although the fracture of ice/metal interfaces was brittle in nature, the evidence o f dislocation slip in ice crystals, as revealed by etching and replica ting, suggests that microplastic deformations occur in the ice compone nt.