Abstract: Carbon fiber composite material energy absorbing box is an important candidate of metal in automobile, and the connection problem with metal parts in automobile assembly is an important direction for studying energy absorption. In order to study the feasibility of the energy absorption box assembly, the pin connection method in mechanical connection is used to first study the energy absorption effect of the opening on the pipe fittings in this paper. The energy absorption performance difference between the composite pipe fittings and the metal fittings is analyzed through the positive and off-axial quasi-static compression experiments and damage observation. During the process, the feasibility of the connection method was studied. It is found that the bottom opening has no significant influence on the energy absorption of the pipe fittings. The hanging pin connection method designed in this paper is not stable and effective energy absorption is not feasible, and the non-dangling pin connection method is feasible, non-dangling pin connection research can be used for further research.

Key words: composite pipe fittings, pin connection, quasi-static compression, energy absorption