Experimental Evaluation of Dynamic Crack Branching in Poly(methyl methacrylate) (PMMA) Using the Method of Coherent Gradient Sensing

Report No. ARL-CR-637
Authors: Pierce Umberger
Date/Pages: February 2010; 76 pages
Abstract: We investigate the experimental setup and methods to evaluate the characteristics of dynamic crack branching in poly(methyl methacrylate) (PMMA). The method of coherent gradient sensing is used to determine crack tip location and crack mode mixity in samples dynamically loaded via a projectile from a gas gun. We study crack propagation velocities as a function of impact velocity and its effect on crack path and branching. We also note the effect of branching on crack velocity as one or more cracks move through a material.
Distribution: Approved for public release
  Download Report ( 13.569 MBytes )
If you are visually impaired or need a physical copy of this report, please visit and contact DTIC.

Last Update / Reviewed: February 1, 2010