Analysis and test study of thermal deformation on a grid reinforced CFRP mirror

Due to the low density and extremely low thermal expansion, carbon fibre reinforced plastic (CFRP) is one of potential materials applied as precise dimension components. High precise structures, such as antenna reflectors and mirrors, require very strict thermal stability. However, the CFRP laminate usually companied with large thermal deformation, because of align error, thickness error, fiber and resin uneven distribution in the preparation. Therefore, a novel grid reinforced structure was adopted to improve stiffness and resistance of thermal deformation. The validity of the design is verified by finite element method. The thermal deformation test based on the vacuum tank verifies the reliability of the finite element analysis results. For 150mm CFRP mirror, the test results show that the thermal deformation RMS is only 16nm when 4.5 raised, so thermal stability is just about 3.5nm/, and satisfied the requirements in high precise structure application. © 2017 International Committee on Composite Materials. All rights reserved