Assessment of 3D woven near‐net‐shaped I‐sections for aeronautical applications: Weave design, manufacture, and mechanical properties under multiple loading conditions

Abstract

The design of composite I‐sections in aerostructures faces a significant challenge with conventional laminates because they are prone to delamination under out‐of‐plane loads. To address this issue, this study investigates the design, manufacture, and mechanical properties of 3D woven near‐net‐shaped composite I‐sections. The study also compares their advantages with equivalent laminates and examines the influence of weave patterns on their mechanical behavior. Specimens were manufactured using the vacuum‐assisted resin transfer molding technique, and quasi‐static tensile, compressive, and bending tests were conducted to assess the properties of I‐sections with three different weave patterns. It finds that the ultimate strength and damage tolerance of the considered design of 3D woven I‐sections are better than the considered design of 2D woven laminated counterparts, and different weave patterns play a significant effect in damage mode and load‐bearing capacity. In addition, using 3D woven preforms to manufacture composite I‐sections also exhibits shortened production time in terms of layup and resin infusion.Highlights The 3D woven I‐sections show improved damage tolerance over 2D counterparts. The design of weave patterns affects the properties of I‐section composites. Using 3D preforms to manufacture I‐sections exhibits shortened production time. Design consideration is proposed for the optimal weave pattern of the I‐sections.