Affiliation: | Department of Mechanical Engineering, The University of New Mexico, Albuquerque, NM 87131, U.S.A. NASA Lyndon B. Johnson Space Center, Houston, TX 77058, U.S.A. |
Abstract: | For both the maximum stress criterion and strain-energy-density-factor (S) theory, fracture angle (the initial angle of crack growth) − θo is predicted by using opening and sliding mate stress intensity factors, k1 and k2. These theoretical predictions are consistent with experimental fracture angles. For the S theory, the crack spreads in the negative θo-direction in a plane for which S is a minimum, Smin. This quantity was obtained analytically. The experimental data of the critical S (Scr) on plexiglass fracture specimens remains essentially constant. |