Stress-Strain Distribution During Transient Heating of a Transversely Anisotropic Material

Four by six-in. transversely anisotropic plates of 1/8 and 1/4-in-thick pyrolytic graphite were subjected to transient heating in an oxyacetylene flame apparatus. At temperatures up to 1500 deg F, the temperature and thermal strain distributions were determined over the length and thickness of the plates. The thermal strains measured with an optical gauge and the analytically determined strains calculated from the three-dimensional thermoelasticity equations for a two-dimensional temperature distribution were found to be in good agreement. The calculated stress distribution indicates that maximum compressive stresses of −1400 psi and −3000 psi were produced in the 1/8-in. and 1/4-in. pyrolytic-graphite plates, respectively.