TITLE:
Numerical Simulation of Mechanical Properties of Nano Particle Modified Polyamide 6 via RVE Modeling
AUTHORS:
J. Huang, M. Uhrig, U. Weber, S. Schmauder
KEYWORDS:
PA 6 Nanocomposite, RVE Modeling, Mechanical Properties
JOURNAL NAME:
Journal of Materials Science and Chemical Engineering,
Vol.3 No.1,
January
21,
2015
ABSTRACT: In this paper the physical influences on the
mechanical behavior of a Polyamide 6 (PA 6)/Mont- morillonit (MMT)-nanocomposite
are examined by a selected structure modification in a numerical parameter study.
Experimental data of tensile tests of three different volume fractions at ambient
temperature are used as reference. These were compared to homogenized stress-strain
curves calculated with 3D representative volume elements (RVE) under periodic boundary
conditions, in which the curve areas are considered until the tensile yield strength
is reached. Besides the influence of filler orientation, exfoliation and its volume
fraction, both adhesive interface behavior between the filler and matrix, and local
partially crystalline interphases around the MMT-plates were also taken into account.
A good approximation of the numerical representation of the experimental curves
was achieved only after the introduction of the 30 - 40 nm thick partially crystalline
interphases with higher stiffness and strength around the MMT-plates. The use of
an exclusively isotropic matrix led to an underestimation of the mechanical values.
The local modifications of the morphology were assumed to be transversely isotropic
both in the elastic and in the plastic region. The transverse plane is defined by
the lateral particle surface. Compared with the experimentally determined values
of the corresponding Young’s Modulus, an excellent correlation was achieved. The
yield strength for the largest volume fraction shows the best agreement with experimental
values.