Fracture toughness determination of bearing steel using chevron-notch three point bend specimen

Stress intensity factor formulas and dimensionless compliance formula of chevron-notch three point bend specimen obtained by use of straight-through-crack assumption (STCA) and Bluhm's slice model have been presented. Two stress intensity factor coefficient formulas have been compared with the experimental data of GCr 15 bearing steel. The comparison has shown that the formula obtained using slice model is in better agreement with experimental data. The plane-strain fracture toughness measurements by chevron-notch specimen and by ASTM E399 standard method have been compared and are in agreement. The effect of slot width of chevron notch on the measurements has been studied.