Investigating the strength of adhesively bonded SMC components

Investigating the strength of adhesively bonded SMC components

Michele Tropeano, Gianluca Gatti, Luca Raimondi, Lorenzo Donati, Davide Serradimigni

Abstract. Sheet Molding Compound (SMC) has emerged as a compelling alternative to light metal alloys to produce lightweight structural components in several industries. Despite their advantages, the complexity introduced by random short-fiber reinforcement SMC materials makes their mechanical behavior challenging to predict using Finite Element Analysis (FEA) models. These challenges extend to evaluating and predicting the bonding strength of adhesive joints involving such materials, which is critical in many automotive and aerospace applications. This research proposes a methodology for generating accurate material cards for adhesives/joints. The approach integrates experimental testing, numerical modeling, and optimization. A three-phase process was employed, utilizing software such as HyperMesh, Abaqus, and HyperStudy. The optimization phase involved the Design of Experiments (DOE) to explore parameter spaces, fitting to construct response surfaces, and optimization algorithms to refine material properties for curve matching. Despite the challenges posed by the brittle nature of SMC substrates, the approach successfully captured the joint’s mechanical behavior, producing a reliable material card for this specific material combination. This study underscores the potential of the proposed methodology to predict joint strength in large-scale simulations, such as full-vehicle assemblies, with improved accuracy and reliability. By addressing the unique challenges of SMC materials, this work provides a robust framework for adhesive characterization and enhances structural designs in composite bonding applications.

Keywords
Sheet Molding Compound, Adhesives, Composite Joining

Published online 5/7/2025, 9 pages
Copyright © 2025 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Michele Tropeano, Gianluca Gatti, Luca Raimondi, Lorenzo Donati, Davide Serradimigni, Investigating the strength of adhesively bonded SMC components, Materials Research Proceedings, Vol. 54, pp 478-486, 2025

DOI: https://doi.org/10.21741/9781644903599-52

The article was published as article 52 of the book Material Forming

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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