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

Cicek K. F., Erdal Erdoğmuş M., Kayran A.

JOURNAL OF COMPOSITE MATERIALS, vol.51, pp.2347-2361, 2017 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 51
  • Publication Date: 2017
  • Doi Number: 10.1177/0021998316669993
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.2347-2361
  • Keywords: Composite laminates, autoclave manufacturing, total spring-in, finite element analysis, total spring-in measurement, optical scanning, PREDICTION, SHRINKAGE, DEFORMATION, DISTORTIONS, WARPAGE, MODEL, CURE
  • Middle East Technical University Affiliated: Yes


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.