A new technique for the manufacture metal matrix composites has recently been developed. This technique produces a structure of a metallic matrix banded structured-layers of multiwall carbon nanotubes by a diffusive processes. To understand the increase in the volumetric mechanical properties of the composite and the dispersion of the nano-reinforcement, a nanomechanical characterization was performed by nanoindentation and atomic force microscopy. From the mechanical tests performed, a stiffness and elastic modulus maps were made near the reinforced areas, then the dispersion of the nano-reinforcements and the homogeneity of the mechanical properties were accessed. The results showed an increase in the modulus of elasticity of up to 150%; and a good dispersion of the nano-reinforcements in the reinforced zone, which demonstrates the feasibility of the alternative manufacturing process for increasing the mechanical properties of the composite.

Metal matrix composites (MMCs) have been a fundamental element in the development of technologies related to the aerospace and automotive industries. This is because they have an excellent weight-to-strength ratio, i.e., they are light materials with a high mechanical resistance. In the manufacturing of MMCs, the incorporation and homogeneous dispersion of reinforcements in the matrix has been one of the biggest challenges. The issue has expanded to the manufacturing of materials reinforced with nano-scaled particles. This study is aimed at the manufacturing, optimization, and characterization of the polymeric matrix reinforced with carbon nanotubes and alumina (hybrid composites), in order to use the polymeric matrix as an inclusion vehicle of the nano-reinforcements in a metallic matrix. The synthesis of the polymeric matrix composites was carried out by a solution mixing technique using polyvinyl alcohol as a matrix. For the reinforcement's dispersion, a magnetic stirring and sonication were used. Finally, the solution was put into a petri dish to allow its polymerization. The nano-reinforcement dispersion qualification and the quantification of the polymer matrix composite were carried out through the tension, nanoindentation, dynamical mechanical analysis test, elastic modulus mapping, and statistical model for dispersion. In addition, a preliminary study of the metallic composite was carried out and was fabricated by the sandwich technique. The initial characterization of the composites was performed through the nanoindentation test.

Oxidative mechanisms in tribological processes are commonly related with temperature and the real contact area. In this article, a lumped parameter dynamic model was developed to predict friction-generated oxide thicknesses in dry sliding conditions. The proposed model is based on conservative principles and causal equations applied to a pin-on-disk configuration in order to calculate the flash temperature with base on the heat transfer phenomena. Also, a mass balance was proposed to estimate the amount of hematite (Fe₂O₃), magnetite (Fe₃O₄) and wüstite (FeO) formed by friction heat. A new equation was proposed to predict the thicknesses of the oxides generated and the model was validated based on experimental data available in specialized literature.