Non-destructive testing of hybrid composite structures
TWI is co-ordinating the ACCURATe project that aims to create the optimum technology for the non-destructive testing (NDT) of present and future generations of aircraft hybrid composite structures. This includes carbon fibre reinforced polymer (CFRP), hybrid polymer-metal multi-layer sandwich structures, structures containing damping or very attenuative materials, as well as thick laminates.
These hybrid composite structures offer much greater fatigue strength-to-weight ratio and elastic modulus to weight ratio than metals, making them fundamental to the reduction of fuel costs and emissions in the aerospace industry. However, they are more expensive and are at greater risk of developing an internal defect and damage leading to structural failure, than regular structures.
The project will create a prototype system, for fast and contactless NDT of these structures, during the manufacturing process. The robot uses a non-contact laser generated and detected pulsed ultrasound technique (LUT), delivering both the laser ultrasound excitation and detection pulses through flexible optical fibres.
For more information, please visit the ACCURATe project website.