A study on the mechanical properties of epoxy resin film using the mark shearing system

An epoxy resin was chosen as the substrate of a grating for a curved surface moiré interferometry study because of its chemical properties and convenience in processing. Considering the low toughness of the epoxy resin, di-n-butyl was used to modify the resin's mechanical properties. A number of films with different amounts of di-n-butyl and undergoing differing lengths of time in the centrifuge were made. The mechanical properties of these films were then studied. A loading apparatus driven by a step motor was used to apply a load and an optical extensometer, based on the mark shearing method, was used to measure the strain of the film. The nominal stress-strain curves of these films were obtained which yielded useful results. The experimental results also demonstrated the feasibility of the testing system for film-like specimen measurements.