μ-CT Based Measurements of the Characteristic Lengths of Polyurethane Foams Employed in the Automotive Industry for Noise Control Applications

L. Bregant1, S. Favretto2, C. Bertolini3

1 Dipartimento di Ingegneria Meccanica, University of Trieste, Italy

2 Dipartimento Materiali e Risorse Naturali, University of Trieste, Italy, Email: sfavretto@units.it

3 Rieter Automotive Menagement AG, Winterthur, Switzerland

ABSTRACT

Cellular materials have many useful mechanical, thermal and acoustic properties but, in order to efficiently employ them, their morphological characteristics need to be related to the engineering performances via numerical models.

In this experimental work the intricate 3D pore space of a large set of polyurethane foam samples used in the automotive industry has been non-invasively investigated using X-ray micro computed tomography (μ- CT) at the SYRMEP beamline of the Synchrotron Light Lab at ELETTRA (Basovizza, Trieste).

The analysis has been proved as an effective method to visualize the microstructure of foam samples with a resolution absolutely adequate to reveal the main features of such kind of materials. Quantitative measurements on reconstructed volumes and precise recognition of geometrical elements were achieved by mean of standard visualization software and custom developed codes.

Keywords cellular material, acoustic foam, X-ray imaging, pore space, digital morphology.