Damage detection by double-sided ultrasonic assessment in low-velocity impacted CFRP plates

Abstract

The use of Carbon Fiber Reinforced Plastics (CFRP) is widely increasing for component design in aerospace. Therefore, a good understanding of the integrity of the damaged components is very crucial. In the present work, a methodology has been applied for reliable depth-related damage detection in CFRP plates under low-velocity impact by using Phased-array Ultrasonic Testing (PUT) technique. Double-sided PUT was utilized to achieve the most reliable damage detection in the impacted CFRP plates. CFRP plates were tested under low-velocity impact ranging from almost 7 J to 27 J by using drop tower. The effect of boundary condition on the induced damage is also investigated. A new boundary condition by using elastomer representing quasi-free boundary condition is proposed for experimental setup of low-velocity impact tests. The elastomer could remarkably reduce the damage caused by the low-velocity impact due to its high elasticity range.