Process Development for Minimization of Spring back Deformation of CFRP Reflector

Abstract

Carbon fiber reinforced polymers are extensively used for manufacturing reflectors because of their high specific strength and specific modulus. Various methods are available for manufacturing reflectors can be broadly classified as prepreg-based methods and non-prepreg based methods. In order to ensure quality, reliability and void-free parts with high fiber volume fractions vacuum bagging of prepegs coupled with autoclave curing is the preferred process for manufacturing reflectors.

During the autoclave curing of the components, defects like warpage and spring back deformation may be generated. The defects are dependent on process parameters like, geometry, the coefficient of thermal expansion, layup sequences, curing cycle etc. The aim of the present work is to determine the effect of process parameters on spring back effect. The parameters like mould material, ply thickness, layup sequence and curing cycle are considered in this study. Before deformation is predicted, the moulds of CI, SS, Invar and Graphite are manufactured. Seventy two experiments are carried out considering effect of the identified process parameters. The profile of manufactured reflectors is measured using 3D scanning technique. The results of experimental work are compared with combined using simulation approach. For the simulation work, COMPRO software is used. For the experimental work, the autoclave curing technique is used. In the design of experiments work, the analysis of variance method of Minitab software is used.

It is noted that invar mould, single hold cycle and [0/45/-45/90] and 2mm thickness result in minimum possible springback.