Failure characterization by pull-out test on structural inserts in sandwich panels used in the aerospace industry applying neutron imaging

Abstract

In the present work, the failure of the inserts potted on the structural sandwich panel used in satellites was analysed. Inserts were tested by pull-out test to evaluate the strength of the joint between the potting mass and the sandwich panel. Neutron experiments were performed in NECTAR, the thermal neutron imaging facility at FRM II. Two series of specimens with dimensions of 10x10x2.5 cm3 and 5x5x2.5 cm3 were tested by applying different normal loads to detect singular points in the load-displacement curves. Images were acquired using thermal neutrons and filtering the beam obtaining images formed by gamma rays and epithermal neutrons. The filter was formed by a cadmiun (Cd) layer on the neutron beam. The results determined the usefulness of this characterization technique to analyse the dynamics failure of the insert union by the use of in-situ experiments in future studies.