Evolution of Interfacial Shear Strength and Mean Intrinsic Single Strength in Biobased Composites from Bio-Polyethylene and Thermo-Mechanical Pulp-Corn Stover Fibers

In this article, with the aim of promoting sustainability, contributing to the circular economy and the fight against climate change, the production of composite materials from Bio-polyethylene reinforced with corn stover fibers has been studied. The behavior of the materials obtained has been studied experimentally and by mathematical models of micromechanics. The composite materials were produced by extrusion and then injection with from 10 to 50 wt.% of fibers. The creation of a good fiber-matrix interface was studied by the incorporation of coupling agent between (0–8 wt.%). Increase of 131.2% on tensile strength for 40wt.% reinforcement was achieved by adding 6 wt.% of coupling agent. The correct interface was demonstrated by a correlation of 0.99 between the experimental results and the results of the mathematical models used.

Download Full-text

Mechanical Property Study of the Fiber-Matrix Interface in SiC/SiC Composites

Materials, Nondestructive Evaluation, and Pressure Vessels and Piping ◽

10.1115/imece2006-15428 ◽

2006 ◽

Author(s):

Eric L. Jones ◽

Sergey Yarmolenko ◽

Devdas Pai ◽

Jag Sankar

Keyword(s):

Shear Strength ◽

Interfacial Shear Strength ◽

Ceramic Matrix Composites ◽

Ceramic Matrix ◽

Interfacial Shear ◽

Fatigue Properties ◽

Matrix Interface ◽

Fiber Matrix Interface ◽

Fiber Matrix ◽

Sic Composites

The fiber-matrix interface between ceramic fibers and ceramic matrix plays a major role in the fatigue properties and toughness of continuous fiber reinforced ceramic matrix composites (CMCs). Boron Nitride (BN) is a widely used fiber coating material that provides a weak bond between the fiber and matrix. A weak fiber-matrix interface increases the strength and toughness of the overall CMC. Single fiber push-out tests were performed to study interfacial shear strength as a main parameter defining fatigue properties and toughness of SiC/SiC composites. The fiber-matrix interfacial shear strength was studied in melt infiltrated Hi-Nicalon/BN(CVI)/SiC composites exposed to various temperature and loading conditions, similar to those that are used in actual applications. Hi-Nicalon fibers with diameters of 13-14.5 μm were pushed out from samples with thicknesses ranging from 125-280 μm using a spherical tip with a 1 μm radius and 90° conical shape. Interfacial shear strength was calculated from sliding load, fiber diameter and sample thickness. Due to significant scattering, 30 individual push tests in every sample were used to obtain the average interfacial shear strength. The virgin sample has a shear strength of 20 MPa which is higher than tensile tested samples (12 MPa). Annealing of a virgin specimen for 100 hours at 1000°C slightly increased shear strength up to 21.5 MPa while annealing at 1100°C and 1200°C led to significant increase of shear strength up to 29 and 39 MPa correspondingly. This effect is associated with BN degradation at temperatures >1000°C.

Download Full-text

Interface Strength and Fiber Content Influence on Corn Stover Fibers Reinforced Bio-Polyethylene Composites Stiffness

Polymers ◽

10.3390/polym13050768 ◽

2021 ◽

Vol 13 (5) ◽

pp. 768

Author(s):

Quim Tarrés ◽

David Hernández-Díaz ◽

Mònica Ardanuy

Keyword(s):

Environmental Impact ◽

Corn Stover ◽

Coupling Agent ◽

Coupling Agents ◽

Future Research ◽

Matrix Interface ◽

Random Orientation ◽

Fiber Matrix Interface ◽

The Impact ◽

Key Parameter

Stiffness of material is a key parameter that allows the use of material for structural or semi-structural purposes. Besides, lightweight materials are increasingly calling the attention of the industry. Environmental impact is also increasing in its importance. Bio-based materials produced from renewable sources can be good candidates for structural purposes combining lightweight and low environmental impact. Nonetheless, similar mechanical properties of commodities have to be reached with such materials. In this work, composite materials from corn stover fibers as a bio-polyethylene reinforcement were produced and tested. The effect of coupling agents to improve the fiber–matrix interface has been evaluated. It has been found that coupling agent content influenced the stiffness of the materials, increasing the Young’s modulus and the material processability. The best performance was achieved for a 6% of coupling agent, corresponding to 4.61 GPa for 50 w/w% of corn stover fibers. Micromechanics showed the impact of the semi-random orientation of the fibers and the lesser impact of its morphology. It was possible to determine a triangular packing of the composites as a hypothesis for future research.

Download Full-text

A Study of the Fiber-Matrix Interface in Composite Materials

Journal of Applied Mechanics ◽

10.1115/1.2899482 ◽

1992 ◽

Vol 59 (2S) ◽

pp. S163-S165 ◽

Cited By ~ 1

Author(s):

Jin O. Kim ◽

Haim H. Bau

Keyword(s):

Composite Materials ◽

Experimental Technique ◽

Stress Waves ◽

Matrix Interface ◽

Fiber Reinforced ◽

Fiber Reinforced Composite ◽

Reinforced Composite ◽

The Matrix ◽

Fiber Matrix Interface ◽

Dispersion And Attenuation

A novel experimental technique for studying the characteristics of the interface between the fibers and the matrix in both undamaged and damaged fiber-reinforced composite materials is described. The experimental technique involves the transmission of stress waves in one or more fibers of the composite. The characteristics of the stress waves, such as speed, dispersion, and attenuation, are measured. These measured variables can be correlated with the characteristics of the bonding between the fiber and the matrix.

Download Full-text