Abstract:
This research is focused on investigating the mechanical behavior of FDM-processed
CFRP/Al hybrid riveted joints at elevated temperatures. A two-pronged approach
was adopted entailing experimental and computational domains. In the experimental
thrust, the developed joint was evaluated for its mechanical behavior by employing
Digital Image Correlation, micro-XCT, and fractographic analysis. The tensile testing
was performed at four different temperatures, i.e., Room Temperature (RT), 50°C,
75°C, and 100°C. At RT, the joint experienced net-sectioning in the CFRP sheet
along with minute secondary bending. Further, distinct failure modes were noticed
for each ply orientation where the inherent porosity/voids appeared as the governing
factor for the damage progression. Novel constitutive models were developed using
accrued strain and change in energy dissipation to estimate the damage progression.
The damage accumulation was found to be more uniform in the 0°layer as compared
to 90°. Moreover, the 90°layer exhibited a more catastrophic damage pattern toward
final failure. At elevated temperatures, a significant reduction in mechanical properties
along with a non-uniform warping/bending of the plies was noticed due to viscoelastic
behavior change. The computational analysis was performed for the validation of the
experimental results and both were found to be in good agreement.
