Volume 20, Issue 5 (September 1992)
Notch Dimensions for Three-Point Bend Fracture Specimens Based on Compliance Analyses
Load-line compliance was calculated for various three-point bend specimens containing finite width notches and cutouts, using methods of engineering strength of materials and elastic superposition. Comparison of compliance results for notched specimens with results for the ideal zero width crack was used to propose two basic notch configurations for fracture testing. A relatively wide notch that could be produced by conventional manufacturing methods resulted in load-line compliance values 10% or more above those of the ideal crack case. A narrow notch that could be produced by electric-discharge machining resulted in compliance values much closer to those of the ideal crack case.