Extrapolation Of Fracture Mirror And Crack-Branch Sizes To Large Dimensions In Biaxial Strength Tests Of Glass

Annealed glass disks were fractured in biaxial tension under a variety of conditions; crack lengths prior to branching and the sizes of the mirror and mist regions were measured. The experimental results indicated the expected correlation between fracture stress and these fracture features, except for an extrapolation to a consistent, clearly defined y-intercept. Neither environment, surface preparation, nor the rate of applied stress was a factor in the fracture stress versus branch, mirror, or mist size relationships.