Measurement of the principal damping components of composite laminates

Abstract

The prediction of material damping in composite laminate components may allow for the development of lighter component designs, and can be achieved via several techniques. One such example, the modal strain energy (MSE) technique requires a combination of effective strain energy modelling and accurate principal loss factor parameters. Measuring principal loss factors can be very challenging for lightly damped components due to parasitic or ‘extraneous’ damping sources introduced by the test set-up itself. To ensure high quality input data to the strain energy models an novel damping test procedure has been developed, which allows for mono-harmonic damping parameter extraction via free decay and logarithmic decrements, whilst minimising extraneous dissipation. Improvements over the established impact hammer testing technique could be shown during the validation of the approach.