Effects of gamma ray irradiation on penetration hole in and fragment size from carbon fiber reinforced composite plates in hypervelocity impacts

Effects of electron beam irradiation on hypervelocity impact behavior of carbon fiber reinforced plastic plates

“…The peeled-off length and width increased with impact velocity. This trend is similar to that of the gamma ray results of Nishida et al 15 (including the first author of this paper). Regardless of electron beam irradiation, the perforation holes were almost circular, which is the same as those of aluminum alloy plates or metal plates, [19][20][21] because the CFRP plates are quasi-isotropic.…”

“…Figure 9 shows several examples of the fragments from the CFRP plates. Regardless of electron beam irradiation, most fragments are slender, which is similar to the results of CFRP without irradiation in the previous studies, 15,24 and are completely different from the fragments scattering from aluminum alloy plates; an example of fragments from aluminum alloy plates is. 25 Fragment length on the impact side seems to be slightly larger than that on the rear side.…”

“…The size distributions of fragments ejected from CFRP plates were examined using the method discussed in the reference, 15 which refers to the direct measurement method. The rear side of the target was surrounded by five plates so that the backward fragments on the rear side of the target could be collected separately from the front side of CFRP plates (hereinafter, this is called impact side).…”

“…On the impact side and rear side, the fragment length at 5.2-5.7 km/s was clearly longer than that at 2.2-2.5 km/s, and the number of fragments at 5.2-5.7 km/s was clearly greater than that at 2.2-2.5 km/s. In general, the fragment length and the number of fragments increase with impact velocity even in the case of CFRP (i.e., 13,15 ) as well as aluminum alloy plates. 12 Even when irradiated specimens were used, the fragment length increased with impact velocity.…”

“…In particular, the authors' research group focused on the combined effects of space environments because of increasing satellite lifespans, and as a first step reported the irradiation effects of gamma ray on the perforation hole size and size distribution of fragments in the hypervelocity impacts. 15 In the present study, fragments from electron beam-irradiated CFRP plates were examined when aluminum alloy spheres struck them. The effects of electron beam irradiation on the perforation hole size of CFRP plates and the size distribution of the fragments ejected from CFRP plates were studied.…”