Design and evaluation of carbon fibre-reinforced launch packages with segmented, copper and molybdenum fibre armatures

Fibre armatures have been studied both dynamically and statically to gain insight into their electrothermal and mechanical behaviour. In the first part of this paper, the results of launch experiments with single and multi-segment copper and molybdenum fibre armatures integrated in carbon-fibre reinforced launch packages are discussed. The launch experiments with Cu fibre armatures showed an improved reproducibility and a higher transition velocity. The poor results of the launch experiments with the Mo fibre armatures thus far, are explained with results of armature compliance and resistance measurements. In the second part, results are presented which are obtained from static experiments in an armature test bed. Using miniature B-dot probes and Rogowski coils, the magnetic field diffusion into monobloc and fibre armatures with identical geometry has been studied. The results show a significant difference in diffusion behaviour between the two types of armatures. It appears that the magnetic field diffuses faster into the fibre armature. The experimental data are compared with the results of calculations of the magnetic field distribution in both armatures based on 2D- and 3D-finite element computer simulations. The results of the 2D-simulations appear to confirm the measured results for monobloc and fibre armatures only qualitatively. The experimental results obtained with monobloc armatures agree with the results of the 3D-simulations in a quantitative sense.