Experimental and numerical study of spring-in angle in corner shaped composite parts

Çiçek, Kerem Furkan
In this study, spring-in problem encountered in corner shaped composite parts which are made of Hexcel’s AS4/8552 unidirectional (UD) prepregs is investigated. For that purpose, a simple two dimensional (2-D) geometrical model available in the literature is implemented and spring-in is calculated according to this model. Then using autoclave process, U-shaped composite parts are manufactured and spring-in measurements are performed on these parts. Finally, a three dimensional (3-D) numerical model in ABAQUS is constructed by taking tool-part interaction, cure shrinkage and state transformations of resin into account and spring-in simulation is performed. Spring angle of 0.92° found by numerical analysis model is found to be in good agreement with the spring angle of 0.85° found by experimental method. Consequently, an efficient 3-D ABAQUS model is developed for spring-in analysis of corner shaped composite parts.


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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 part...
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Citation Formats
K. F. Çiçek, “Experimental and numerical study of spring-in angle in corner shaped composite parts,” M.S. - Master of Science, Middle East Technical University, 2014.