Fracture Energies of Sintered Boron Nitride

Abstract

Fracture energies of a sintered boron nitride were measured using chevron-notched compact tension type specimens. During stable crack growth unloading-reloading processes were repeated in order to evaluate the plastic deformation. From load P-loadpoint displacement u diagram, total fracture energy (work of fracture) γ_WOF was determined as 26.2J/m² with error of less than 5%, close to a half of which (about 45%) was found to be dissipated by plastic deformation. The results were discussed in the relation with those on graphite materials.