Study on molding Process for hat-stiffened composite panels

Abstract

In this paper, the hot diaphragm performing process for the pre-forms of composite hat-stiffened stringers was studied. The effects of molding temperature, deformation rate and diaphragm on hot diaphragm performing process were analyzed. The results showed that the pre-forms of composites hat-shaped stringers were manufactured successfully through hot diaphragm performing process and then they were cured by the autoclave. The pre-forming temperature was 75°C and the cured stringers met the requirement of the nondestructive testing. The molding temperature and vacuum rate were optimized simultaneously to ensure that prepreg had best ability to slip. Increasing thickness and stiffness of the diaphragm could significantly improve the molding quality of hot diaphragm performing process. Finally, the hot-shaped stringers and the skin of the composite hat-stiffened composite panels were assembled and then they were successfully prepared by the co-bonding process, which effectively reduced the manufacturing cost of the composites.