Mixed-Mode Testing for an Asymmetric Four-Point Bending Configuration of Polyurethane Foams

Abstract:

Many efforts have been made recently to determine the fracture toughness of different types of foams in static and dynamic loading conditions. Taking into account that there is no standard method for the experimental determination of the fracture toughness of plastic foams, different procedures and specimens were used. This paper presents the polyurethane foam fracture toughness results obtained experimentally for three foam densities. Asymmetric four-point bending specimens were used for determining fracture toughness in mode I and in a mixed one, and also the influence of the loading speed and geometry of the specimen were investigated.

• Periodical: Applied Mechanics and Materials (Volume 760)
• Pages: 239-244
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.760.239
• Online since: May 2015
• Authors: Dragoş Alexandru Apostol, Dan Mihai Constantinescu*, Liviu Marsavina, Emanoil Linul
• Keywords: Asymmetric Four-Point Bending, Mixed-Mode, Polyurethane Foams

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