An investigation on fracture toughness of graphite using test and numerical methods

摘要

The fracture toughness of graphite was measured by three point bending tests on single edgenotched beams (SENB) at room temperature.The test specimens were cut from different blocksat different positions and directions in order to study the dispersion of the fracture toughnessand the anisotropy of the graphite.To investigate the effect of specimen geometry on fracturetoughness,specimens with different sizes and different notch depths were used.Fracture toughnessincreased with increasing specimen size and decreased with increasing notch depth.The strainfield on surface of the specimen was measured using digital speckle correlation method (DSCM)and strain gauges.A finite element analysis was carried out according to the actual geometry ofthe test specimens and the numerical results have been compared with the test results.