Ismeli Alfonso

In this work, heat treatments were applied to Al-5%Li alloys, varying times and temperatures, which ranged between 8 and 16 h, and 450 and 600 °C. This led to microstructural changes derived from diffusion in the Al-Li eutectic phase and its transformation. The processes of fragmentation, spheroidization, and coarsening were observed, and even localized melting when heat treatment temperatures above the eutectic line were used. These results showed that, depending on the heat treatment conditions, microstructural modifications can occur to obtain different mechanical properties, but they can also cause porosity, which may be used as a starting point for producing metallic foams from these alloys, expanding their applications.

The National Congress on Frontier Materials (CONAMAF) was successfully established in 2025 as a new national initiative. In its first edition, it was held at the UNAM Morelia Campus and organized by the Morelia Units of the Institute for Materials Research and the National School of Higher Studies of UNAM. This event emerged as a viable alternative for the Mexican scientific community, creating a multidisciplinary forum for students, academics, and professionals to discuss advances and applications across the broad spectrum of materials science. Although this event was conceived with a national scope, it featured speakers from across the country and authors from 10 different countries, including Latin America, France, Germany, and the United States, reaffirming its international character and the quality of the research presented. CONAMAF integrated the 20th School of Materials Science and Nanotechnology and the 19th University-Industry Forum, through which undergraduate and graduate students received practical training, learned new methodologies, and established networks for their professional development and links with the productive sector. This effort not only fosters interdisciplinary collaboration but also helps position Mexico as a leader in the development of advanced materials.

This work studies possible morphologies present in fractal foams with dual pore distribution, focalizing the analysis in features characterizing the pore network. These studies were conducted using foams modelled through the combined use of Discrete and Finite Element Methods (DEM and FEM, respectively). DEM was used to generate pore coordinates, for in a second step modelling pores of varied sizes using FEM. These models allowed to obtain fractal foams with morphologies closer to real experimental foams, which is essential for the subsequent estimation of their mechanical properties through FEM. Using different measurement methods, some analyzes were carried out, such as the effect of the dimension of the Representative Volume Element (RVE) on the porosity percentage, the number of nodes until a convergent behavior, the interconnectivity of the pores, the importance of the pore wall thickness and the fractal dimension determination. The effect of these parameters on the simulated mechanical properties of the foams was analyzed throw the use of FEM.

Aluminum foams excel as versatile materials by combining porous structures with aluminum alloys properties. The infiltration method provides precise control over pore size and distribution, but depends on space holder particles (SHP) characteristics. This study examines the influence of SHP morphology on the structural and mechanical properties of infiltrated aluminum foams. Al-319 alloy was used with NaCl SHPs (∼5 mm of equivalent diameter) with three morphologies: spherical, ellipsoidal, and irregular. Structural characterization included density measurements, image analysis, and computed tomography. Uniaxial compression tests revealed that foams with granulated pores had the lowest properties (E = 1.15 GPa, σ _pt = 13.19 MPa, E _abs = 7.51 MJ/m³), while spherical pores maximized energy absorption (10 MJ/m³) due to improved load distribution.

The self-foaming method offers a promising approach for producing AlCuFe metallic foams without the need for external foaming agents. Although it is well established that both alloy composition and heat treatment play a fundamental role in pore formation, the specific influence of annealing time on the resulting microstructure and physical properties remains insufficiently explored. In the present study, the effects of annealing time on the microstructure, phase evolution, and magnetic properties of self-foaming Al₅₈Cu₂₇Fe₁₅ alloys are investigated. Metallic foams were synthesized using the self-foaming method, heat-treating the samples at 850 °C for 6, 9, 15, and 24 h. X-ray diffraction (XRD), differential thermal analysis (DTA), and scanning electron microscopy (SEM) reveal that prolonged annealing increases porosity, reaching 64% and 61% after 15 and 24 h, respectively. The porosity formation mechanism was attributed to a peritectic reaction involving the liquid metastable τ phase and the solid λ and β phases. Magnetic measurements indicated complex behavior consistent with the Curie–Weiss law, influenced by phase composition and interactions between Coulomb forces, Hund’s rule exchange, and Fe 3d–Al s, p orbital hybridization.

Functionalized polynorbornenes are very important specialty materials for a wide variety of practical and industrial applications. In the membrane technology field, polynorbonene derivatives play a main role in gas transport since they can be systematically and easily functionalized, thus affecting the membrane performance in gas separation processes. Thus, several methodologies have been employed to yield macromolecular architectures with tailored gas permeation properties. This review is intended to provide different synthesis routes of substituted polynorbornenes as well as the effects of the polymer chemical structures on their gas permeation properties, among others.