Title: Shape Compensation of Stamp Formed Thermoplastic Composites

Authors: Eduardo Barocio, Justin Hicks, Garam Kim, Johnathan Goodsell, R. Byron Pipes

DOI: 10.33599/nasampe/s.24.0235

Abstract: Shape change in stamp forming of laminated thermoplastic composites is caused by multiple phenomena that includes anisotropic shrinkage and process induced stresses. The geometrical deviation in a stamp formed component can be such that significant miss-fitting stresses will develop upon fitting the component in the intended nominal shape. Traditionally, an iterative tool design process would be carried out, wherein the stamp forming matched metal tooling is modified until a compensated tool shape that will produce the nominal stamp formed shape is achieved. To reduce the tool development cost and accelerate the process development for stamp forming, a physics-based virtual twin of the stamp forming process, termed FORM3D, has been developed. Predictions of FORM3D were validated against experimental measurements for a double curvature quasi-isotropic laminate geometry. The double curvature geometry developed both spring-in and spring-out deformations in the minor and major radii of curvature, respectively. FORM3D predictions were in excellent agreement with the experiments in both magnitude and distribution of the deformation. Furthermore, FORM3D was utilized to determine the tooling geometry required to produce the desired part geometry in a single step process. The part geometry produced with the compensated tool was shown to agree with the desired part geometry within ±0.25 mm. This enables replacement of the experimental iteration with numerical iteration, augmented with physical insights gained through physics-based modeling; both serve to decrease development cost and time.

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Conference: SAMPE 2024

Publication Date: 2024/05/20

SKU: TP24-0000000235

Pages: 9

Price: $18.00