6 research outputs found
Three-dimensional in situ observations of compressive damage mechanisms in syntactic foam using X-ray microcomputed tomography
Syntactic foams with hollow glass microspheres embedded in an epoxy matrix are
used in marine, aerospace and ground transportation vehicle applications. This
work presents an in situ experimental study of failure mechanisms in syntactic
foam based on X-ray microcomputed tomography with uniaxial compression.
Under different levels of compressive strain, the material was scanned using X-ray
microcomputed tomography to obtain three-dimensional (3D) images of its
internal microstructure. Experiments with the same parameters were carried out
to investigate repeatability. The microscopic observations have suggested that
damage nucleation occurs at the weakest microspheres. When applied strain
increases, shear collapse bands (SCBs) develop local to the fragmented microspheres
due to stress concentration and bending deformation around SCBs occurs.
After significant strain, the thickness of the SCBs increases owing to the accumulation
of the broken microspheres. The relationship between the volume
fraction of microspheres and applied bulk strain has been characterised