Large deployable reflectors usually use knitted metal mesh reflecting surfaces. Knitted metal meshes are characterized with excellent stowability properties. At the same time meshes have to be tensioned therefore accuracy gets degraded. In order to keep the stowability advantages of knitted meshes but enhancing shape accuracy a flexible reflecting surface material composed of Carbon Fibre Reinforced Silicone (CFRS) has been developed and investigated. Due to its small bending stiffness determined by the silicone matrix the composite material can be manufactured in relatively straightforward process with double curvature and nearly ideal parabolic shape. Compared to the conventional stiff matrix composites, which give high accurate double curved reflecting surfaces, an additional functionality is acquired by using a flexible silicone matrix and easy stowing and deployment is achieved. Because of carbon fibres the CFRS is characterized with a very low thermal expansion coefficient (measured and calculated about -0.36e-6/C) with no moisture absorption or micro-cracking effects even under strong environmental cycles. It points to a high dimensional stability of the material. Results obtained from different thermo-mechanical and RF characterization tests for such CFRS surfaces confirm the expected behaviour. The measured RF properties as insertion loss, cross-polarization, reflectivity, and PIM show that the created material can be used even up to 15 GHz RF. Higher frequencies can be achieved in particular cases. Several application examples are addressed further in the paper.
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