Moiré interferometry for thermal expansion of composites

Techniques were developed for high-sensitivity moiré interferometry by reflection, using a real reference grating of 1200 lines/mm (30,000 /in.). Coefficients of thermal expansion of selected graphite-epoxy laminates were determined in the temperature range of 297 K (75°F) to 422 K (300°F). Very good precision was achieved for a wide range of thermal-expansion coefficients, from approximately zero to 27 /K.D.E. Bowles was a Graduate Student at Virginia Polytechnic Institute and State University when this research was conducted; is currently Materials Engineer at NASA-Langley Research Center, Hampton, VA 23665Paper was presented at 1981 SESA Spring Meeting held in Dearborn, MI on May 31–June 4.