Experimental and numerical study of process-induced total spring-in of corner-shaped composite parts

Process-induced total spring-in of corner-shaped composite parts manufactured via autoclave-forming technique using unidirectional prepreg is studied both numerically and experimentally. In the numerical study, a three-dimensional finite element model which takes into account the cure shrinkage of the resin, anisotropic material properties of the composite part and the tool-part interaction is developed. The outcome of the numerical model is verified experimentally. For this purpose, U-shaped composite parts are manufactured via autoclave-forming technique. Process-induced total spring-in, due to the combined effect of material anisotropy and tool-part interaction, at different sections of the U-shaped parts are measured with use of the combination of the three-dimensional optical scanning technique and the generative shape design. Total spring-in determined by the numerical model is found to be in good agreement with the average total spring-in measured experimentally. The effect of tool-part interaction mechanism on the total spring-in is studied separately to ascertain its effect on the total spring-in behavior clearly. It is shown that with the proper modeling of the tool-part interaction, numerically determined total spring-in approaches the experimentally determined total spring-in.


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Citation Formats
K. F. Cicek, M. Erdal Erdoğmuş, and A. Kayran, “Experimental and numerical study of process-induced total spring-in of corner-shaped composite parts,” JOURNAL OF COMPOSITE MATERIALS, pp. 2347–2361, 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/40234.