International Journal of Materials

ISSN: 2313-0555
Volume 5, 2018

Notice: As of 2014 and for the forthcoming years, the publication frequency/periodicity of NAUN Journals is adapted to the 'continuously updated' model. What this means is that instead of being separated into issues, new papers will be added on a continuous basis, allowing a more regular flow and shorter publication times. The papers will appear in reverse order, therefore the most recent one will be on top.

Main Page

Submit a paper | Submission terms | Paper format


Volume 5, 2018

Title of the Paper: Prediction of Effective Mechanical Properties of Composite Materials Using Homogenization Approach: Application to Tungsten Fiber Reinforced Bulk Metallic Glass Matrix Composite


Authors: Soufiane Belhouideg

Pages: 8-12

Abstract: In this paper, the homogenization approach was presented to predict the effective mechanical properties of heterogeneous materials such as composite materials. Indeed, the main idea of this approach is to characterize the effective mechanical properties from a microstructural description of the heterogeneous materials and the knowledge of the local behavior of constituents using the homogenization process. It is a very efficient tool which is intensively developed in the field of numerical simulation of heterogeneous materials. Different scheme established from the solution of Eshelby’s inclusion problem are recalled such as Mori-Tanaka scheme, dilute scheme and Voigt and Reuss bounds. Homogenization approach was applied to estimate the effective mechanical properties of tungsten fiber reinforced bulk metallic glass matrix composite. Predicted values were confronted with those obtained by experimental approach from literature. These comparisons show good agreement between the predicted and experimental values. The maximum deviations remain lower than 10.5% using Voigt bound. A parametric study shows that the mechanical properties depend strongly on the shape of inclusions.

Title of the Paper: Effect of Organic Solvents in Morphology and Mechanical Properties of Electrospun Polyvinylpyrrolidone Fibers


Authors: Christian Narváez-Muñoz, Nathaly Villacís, Diego Narváez, Karla Vizuete, Carlos Arroyo

Pages: 1-7

Abstract: In this work, the electrospinning technique was used to obtain fibers for mechanical characterization. polyvinylpyrrolidone (PVP) was combined with organic solvents (ethanol and dimethylformamide (DMF)) to generate solutions, looking for the appropriate parameters to obtain fibers with the best morphology and the best mechanical properties. Starting from previous investigations to find the adequate percentages of solvent and PVP, several solutions were made, varying the different parameters like voltage, flow, tip collector distance. Seeking to obtain acceptable samples, the diameter was measured in a scanning electron microscope (SEM). The elastic modulus was measured for the fibers with the best aspect. Mechanical properties were measured in an atomic force microscope (AFM) with the Hertz contact method and the data were approximated to its mathematical model. The solutions that resulted in the best morphological properties were: ethanol - 8% PVP, DMF – 14% PVP, 70% ethanol - 30% DMF - 8% PVP, with diameters in the micrometer range of 1.6, 1.22 and 1.35 respectively, and elastic modulus of 40.08 MPa, 8.8 MPa and 32.78 MPa correspondingly. An analysis of all the parameters influencing the process was performed and an analysis of the influence of the solvents, based on the data of the elastic moduli was carried out.