DataVXJournal of Materials SciencePaper
journal article·2025-06Open access

Simulation of steel/epoxy laminates for electric engines or generators: part 2—experimentally and numerically established temperature-dependent cohesive zone model

Martin Tiefenthaler, Gernot M. Wallner, Cornelia Marchfelder, Bernhard Strauß, Martin Rosner

Journal of Materials Science· Volume 60· Issue 24
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Abstract

Abstract Two waterborne varnishes with an epoxy equivalent weight (EEW) of ~ 500 and ~ 900 g/mol were used for preparation of full-surface-bonded electrical steel laminates. By digital image correlation (DIC)-assisted testing, a nonlinear temperature dependency of the thermal expansion coefficient was ascertained for the laminates. Using double cantilever beam (DCB) specimens and DIC-assisted crack opening measurement, temperature-dependent critical energy release rate (GIc) and J-integral (JIc) values were determined. The laminates with the higher EEW epoxy revealed higher GIc values. Up to 60 °C, high monotonic crack growth resistance was confirmed for both laminates. The GIc and JIc values were a factor of 10 lower above Tg of the epoxy. The data were used to implement and validate a temperature-dependent cohesive zone model (CZM) based on a bilinear traction–separation law. Such models are essential for the simulation of full-surface-bonded electric engine laminates. Graphical abstract
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Research context

Metals & alloysComposites

OpenAlex topics: Mechanical Behavior of Composites · Epoxy Resin Curing Processes · Composite Structure Analysis and Optimization

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

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