Mechanical Properties of Polypropylene/Carbon Nanotube Composites by Indentation Technique

Abstract:

The Instrumented Indentation Technique (IIT) is used to measure the local mechanical properties of different materials. The mechanical parameters (indentation hardness and modulus) of multi-walled carbon nanotubes filled polypropylene (PP/MWCNTs) nanocomposites derived from the load-displacement indentation curve are investigated by sharp indentation. The effect of the visco-elastic-plastic deformations on the mechanical properties is studied considering a 5-step indentation test. The mechanical properties calculated based on the traditional Oliver and Pharr method are compared with those extracted from the new indentation methodology. During the 5-step indentation test, the viscoelastic deformations during the reloading-holding phases are reduced due to the decrease in the indentation displacement with the increase in the concentration.

• Periodical: Advanced Materials Research (Volume 1128)
• Pages: 115-122
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1128.115
• Online since: October 2015
• Authors: Alina Mihaela Cantaragiu*, Catalin Fetecau
• Keywords: Mechanical Properties, Polypropylene, Sharp Indentation, Visco-Elasticity

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