Comparison between quasi-static indentation testing and drop-weight impact testing on delamination onset damage

To discuss the delamination onset load, quasi-static indentation tests and drop-weight impact tests were performed. The effects of the material and plying pattern on the delamination onset load were also studied. Moreover, the delamination threshold energy levels were found and the corresponding damage was analyzed. The results show that the delamination onset load increases along with the impact energy, and the delamination onset load in the quasi-static indentation is lower than in the low-velocity impact. Massive delamination happens in laminate panels when the energy reaches the delamination threshold energy, and the rigidity descends rapidly.