Theoretical and Experimental Investigation on Mechanical Properties of 3-D Braided Composites

摘要

This paper is aimed at elucidating the processing-property relations of composites through experimental characterization. The yarn architecture of three-dimensional (3-D) braided composites products by the four-step 1 1 braiding technique and their effective elastic properties have been studied with experimental investigation and a numerical method, respectively. A series of fabrics with varying braiding fibers, pitch lengths has been made to investigate their respective influence on processing and mechanical behavior. The material characterization has been carried out on the basis of tension and flexure tests. A methodology based upon the concept of fabric unit cell structure has been developed for studying the elastic properties of three-dimensional braided composites. The composite moduli have been analyzed by using the fabric architecture model and compared with experimental results. Numerical examples and experimental results of elastic properties for three-dimensional braided composites are presented.