Influence of impact-induced reaction characteristics of reactive composites on hypervelocity impact resistance

The need to improve the protection capability of spacecraft shield structure is urgent, owing to the deterioration of space environment caused by orbital debris. Reactive material is a kind of impact-induced energetic composites, and using reactive material to protect spacecraft against hypervelocity impact of orbital debris is a new way. In this paper, the dynamic compression experiments of PTFE (polytetrafluoroethylene)/Al (aluminum) and PTFE (polytetrafluoroethylene)/Ti (titanium) reactive materials were carried out. The mechanical properties and impact-induced reaction characteristics of PTFE/Al and PTFE/Ti were compared. The experiments of projectiles with hypervelocity impact on Whipple shields with PTFE/Al, PTFE/Ti and Al2024 as bumper respectively were carried out by using two-stage light-gas gun, and the protective capability of these two reactive materials against hypervelocity impact are compared. The experimental results show that the protective capability of PTFE/Al and PTFE/Ti reactive materials is better than that of Al2024, and the protective capability of PTFE/Al reactive material is better than that of PTFE/Ti. Through theoretical calculation and numerical simulation, the reasons for the difference of protective capability of different reactive materials are analyzed, and the ballistic limit curves of Whipple shield structures are compared. (C) 2020 The Authors. Published by Elsevier Ltd.