Effect of shallow straight-joint braided fabric geometrical parameters on fiber volume fraction

Abstract This research paper establishes the relationship between fabric parameters and fiber volume fraction through analyzing the representative unit cell of the 2.5D shallow straight-joint preform. The effect of fabric parameters on the fiber volume fraction by theoretical study is also investigated. The 2.5D shallow straight-joint fabric was manufactured by quartz fiber to verify the fiber volume fraction by theoretical and experimental study. The errors between predicted and measured results is only 2.12% and 1.13%. It was also found that as warp density and linear yarn density of yarn decrease and fabric thickness increases, the overall fiber volume fraction and weft yarn fiber volume fraction increase, but warp yarn fiber volume fraction decreases. Weft yarn has greater influence on fiber volume fraction of fabric than warp yarn in the structure of shallow straight-joint.