Nanoclay assisted strengthening of the fiber/matrix interface in functionally filled polyamide 6 composites

Isitman, Nihat Ali
AYKOL, Muratahan
Kaynak, Cevdet
This study describes the contribution of a nano-filler, i.e. an organically modified layered silicate, in respect of the fiber/matrix interfacial shear strength (IFSS) of a short glass fiber reinforced and functionally filled polyamide 6, given an exfoliated nanocomposite morphology. Apparent IFSS values are determined using a continuum micromechanical method. Polymer chains in the nanoconfined environment of an exfoliated clay nanocomposite are found to crystallize preferentially in the form of a specific crystalline phase with increased degree of crystallinity. Strong dependence of IFSS on polymer crystallinity is found which is related to enhanced shrinkage stresses associated with increased degree of crystallinity.


Design of fiber-reinforced composite pressure vessels under various loading conditions
Levend, P; Katirci, N (Elsevier BV, 2002-10-01)
An analytical procedure is developed to design and predict the behavior of fiber reinforced composite pressure vessels. The classical lamination theory and generalized plane strain model is used in the formulation of the elasticity problem. Internal pressure, axial force and body force due to rotation in addition to temperature and moisture variation throughout the body are considered. Some 3D failure theories are applied to obtain the optimum values for the winding angle, burst pressure, maximum axial forc...
Stress redistribution around fiber breaks in unidirectional steel fiber composites considering the nonlinear material behavior
SABUNCUOĞLU, BARIŞ; Mutlu, Çağlar; Kadıoğlu, Fevzi Suat; Swolfs, Yentl (Elsevier BV, 2020-05-01)
The use of steel fibers as reinforcement in polymer composites is recently increasing thanks to their ductility, high stiffness and wide range of diameters. Unlike carbon and glass fibers, steel fibers often end up with a non-circular cross-section due to their manufacturing technology. This may influence the stress redistribution around fiber breaks, which is important in longitudinal tensile failure of unidirectional composites. A parametric study was performed by using 3D finite element models with rando...
Isotropic-Kinematic Cyclic Hardening Characteristics of Plate Steels
Shakeri, Ashkan (Springer Science and Business Media LLC, 2017-03-01)
Cyclic hardening of metals is considered as one of the most important features that affects extremely the hysteresis behavior of steel structures. One approach to study this characteristic is dividing it into two components, including isotropic hardening and kinematic hardening, and defining any of these components for any type of metals by calibrated data obtained from experiments. However, the lack of these calibrated data on metals, restricts this approach. Therefore, in this paper the isotropic and kine...
Comparison of damage mechanisms in curved composite laminates under static and fatigue loading
Tasdemir, B.; Çöker, Demirkan (Elsevier BV, 2019-04-01)
In this paper, damage progression in curved CFRP composite laminates are experimentally investigated for static and fatigue loadings. Two different cross-ply laminate thicknesses are examined with grouped plies to elucidate the failure mechanisms. A test fixture is designed to apply moment/axial combined loading to curved specimens and DIC method is used to obtain the strain distribution in the curved region until failure. Our major finding is that under fatigue loading, the failure location and mechanism a...
Interfacial Strength in Short Glass Fiber Reinforced Acrylonitrile-Butadiene-Styrene/Polyamide 6 Blends
Isitman, Nihat Ali; Aykol, Muratahan; Ozkoc, Guralp; Bayram, Göknur; Kaynak, Cevdet (Wiley, 2010-03-01)
The purpose of this study is to derive the apparent interfacial shear strength of short glass fiber reinforced acrylonitrile-butadiene-styrene/polyamide 6 (PA6) blends with different PA6 contents. Tensile stress-strain curves and fiber length distributions are utilized within a continuum micromechanics approach which involves a unified parameter for fiber length distribution efficiency represented as a function of strain. The unique combination of predicted micromechanical parameters is capable of accuratel...
Citation Formats
N. A. Isitman, M. AYKOL, and C. Kaynak, “Nanoclay assisted strengthening of the fiber/matrix interface in functionally filled polyamide 6 composites,” COMPOSITE STRUCTURES, pp. 2181–2186, 2010, Accessed: 00, 2020. [Online]. Available: