Viscoelastic modeling and characterization of thin-ply composite laminates

Thin-ply composite laminates are promising materials for deployable spacecraft structures owing to their low mass and high folding curvature. However, the deployment force and the shape accuracy of the deployed configuration after a long duration of stowage is adversely affected by the inherent viscoelastic behavior of the polymer matrix. This paper presents a computational and experimental investigation into the effective viscoelastic response of thin-ply composite laminates made of woven carbon fabrics and an epoxy matrix intended for deployable spacecraft applications. A two-scale homogenization approach is utilized to model thin-ply composites as viscoelastic plates represented with relaxation ABD matrices. Micrographic analysis and relaxation tests are conducted to obtain the geometric and material characteristics that are incorporated into the model. The bending relaxation behavior is experimentally characterized using the recently developed column bending test methodology to compare against model predictions. The relaxation response is studied in two different orientations. The effects of ply phase arrangement, laminate thickness, fiber volume fraction, specimen width, and coordinate rotation are investigated.

Automated summary

This study investigates the effective viscoelastic response of thin-ply composite laminates for deployable spacecraft applications through computational and experimental methods. A two-scale homogenization approach is utilized to model the materials, with experimental validation of the model predictions.