Investigating the Mechanical and Thermal Relationship for Epoxy Blends
The mechanical response of epoxy networks was investigated under uniaxial compression at low, intermediate, and high strain rates. These epoxy blends are tailored to achieve a broad range of glass transition temperatures. Previous studies have shown a correlation of the epoxies’ Tg in relationship to its ballistic performance as well as its mechanical properties at quasi-static rates. To better understand these phenomena, a MWIR camera was used to directly measure the transient surface temperature and determine temperature change. The extent and rate of deformation highly influences the flow stress behavior which coincides with the rise in the adiabatic temperatures, hence the thermal softening response. One intriguing aspect for results at rates 0.01/s – 0.1/s and higher reveals that the surface temperature continues to increase despite pressure ceasing. This would indicate the core temperatures are still gradually transferring to the surface. The experimental setup and results are discussed.
KeywordsDigital image correlation Epoxy Glass transition temperature Hopkinson bar Thermal imaging
This research was supported in part by an appointment to the Postgraduate Research Participation Program at the U.S. Army Research Laboratory administered by the Oak Ridge Institute for Science and Education through an interagency agreement between the U.S. Department of Energy and USARL.
- 3.Whittie, S., Moy, P., Schoch, A., Lenhart, J., Weerasooriya, T.: Strain Rate Response of Cross-Linked Polymer Epoxies under Uni-Axial Compression. Proceedings of the 2011 Annual Conference on Experimental and Applied MechanicsGoogle Scholar
- 4.Whittie, S., Moy, P., Gunnarsson, C.A., Knorr, D., Weerasooriya, T., Lenhart, J.: Fracture Response of Cross-Linked Epoxy Resins as a Function of Loading Rate. Proceedings of the 2012 Annual Conference on Experimental and Applied MechanicsGoogle Scholar