b. SEM analysis
As expected, for the TEPs-modified specimens the surface was seen to be more irregular indicating a higher deformation, i.e. the material is more ductile (as the yield strength is lowered, the fracture is more ductile in nature). The particles dispersion and sizes were also examined. Also, it was evident that the TEPs-modified adhesive samples showed a uniform dispersion of particles.
2. DCB tests
a. DCB failure mode
After the tests, the failure modes of the specimens were evaluated visually.