In-situ full-field deformation analysis of injection-molded microcellular polycarbonate according to foam morphology patterns

• Published in: Polymer testing Vol. 124; p. 108102
• Main Authors: Güzel, Kübra, Zarges, Jan-Christoph, Heim, Hans-Peter
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.07.2023; Elsevier
• Subjects: Digital image correlation; Foam injection molding; Foam morphology; Polycarbonate; Strain localization; Tensile test; Strain localization; Foam injection molding; Digital image correlation; Polycarbonate; Tensile test; Foam morphology
• ISSN: 0142-9418; 1873-2348
• DOI: 10.1016/j.polymertesting.2023.108102

Deformation behavior of microcellular foam materials are sensitive to microstructural details. Therefore, the distinctive foam morphology patterns of foam injection-molded Polycarbonate are identified. These morphology patterns are investigated regarding their cell size, distance between cells, cell density, density reduction, homogeneity of cell size distribution, sphericity of cells and cell volume. Consequently, the predefined foam morphologies, the resulting modulus of elasticity and the elongation at break are compared to understand extensively how the deformation of foam structures depends on morphological properties. The detection and propagation of cracks are monitored using a 3D Digital Image Correlation technique. According to results, the morphology patterns which are presenting identical mechanical properties, exhibit distinctive differences during crack initiation and propagation. The highly localized strain distribution becomes more inhomogeneous beyond the yield point. Differences in the homogeneity as well as the distance between cells lead to dissimilarities in the localized high-strain fields. •Heterogeneous deformation of different thermoplastic cellular morphologies are observed with a full-field strain measurement.•Differences in cell size distribution and distance between cells lead to dissimilarities in the localized high-strain fields.•Morphology patterns with identical mechanical properties, show distinct differences during crack initiation and propagation.•Crack propagation continues linearly instead of merging with existing cracks in case of non-uniform cell distribution.