Abstract:With the increasing demand of light structure composite in industry, carbon and glass fibres are more and more used, because of their light mass, high strength, high temperature endurance and erosion resistance. This paper focuses on the process of forming a preform. Up to the finished preform, the multilayer reinforced fabrics are subjected to the following procedures: pattern design, cutting and sewing. Considering the fabric properties, the 3-dimensional CAD software and sewing machines, which are generally used in the clothing industry, are also suitable for the processing of the reinforced fabrics. This study aims also to the changes of property arising from the sewing process. Bending stiffness and changes of thickness after sewing are studied. These properties will provide input data for CAD pattern design. 

Key words: 3D reinforcement; textile preform; bending stiffness; thickness; CAD