Damage Degradation Behavior of Wave‐Absorbing Efficiency for Honeycomb Sandwich Structure under Large‐Angle Oblique Incidence

Honeycomb sandwich structure with tunable electromagnetic parameters serves as an important load‐bearing, stealth‐shielding integrated component in the domain of aviation equipment. To cope with the long‐range detection of radar detection technology, honeycomb sandwich structure with wide operating bandwidth and excellent wave‐absorbing efficiency has ongoingly sparked large global attention. Damage degradation behavior of wave‐absorbing efficiency is also a critical indicator parameter, but rarely conduct in‐depth discussions. In this work, a honeycomb sandwich structure with multiple discrete resonant absorption peaks is proposed and the reflection loss is less than −10 dB in 4–18 GHz frequency band. Enhanced wave‐absorbing efficiency is observed for penetrating damage mode with increasing incidence angle in 0°–60° compared with no damage mode. The corresponding damage degradation mechanism is revealed by decoupling surface reflection, bottom reflection of electromagnetic wave, ratio of inherent absorption and interference cancellation. This work provides valuable insights for the assessment of wave‐absorbing efficiency degradation behavior of honeycomb sandwich structure.