@article{MiclosinaBeluNicaCiubotariuetal.2025, author = {Miclosina, Calin-Octavian and Belu-Nica, Remus and Ciubotariu, Costel-Relu and Marginean, Gabriela}, title = {Processing and Evaluation of an Aluminum Matrix Composite Material}, series = {Journal of Composites Science}, volume = {2025}, journal = {Journal of Composites Science}, number = {9(7), Special Issue Metal Composites, Volume II}, publisher = {MDPI}, doi = {10.3390/jcs9070335}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:1010-opus4-48135}, pages = {1 -- 12}, year = {2025}, abstract = {Abstract This study signifies the development and characterization of a composite material with a metallic matrix of aluminum reinforced with a steel mesh, utilizing centrifugal casting technology. An evaluation was conducted to ascertain the influence of the formulation process and the presence of the insert on the mechanical behavior with regard to tensile strength. The aluminum matrix was obtained from commercial and scrap alloys, elaborated by advanced methods of degassing and chemical modification. Meanwhile, the steel mesh reinforcement was cleaned, copper plated, and preheated to optimize wetting and, consequently, adhesion. The structural characterization was performed by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy analyses (EDX), which highlighted a well-defined interface and uniform copper distribution. The composite was produced by means of horizontal-axis centrifugal casting in a fiberglass mold, followed by cold rolling to obtain flat specimens. A total of eight tensile specimens were examined, with measured ultimate tensile strengths ranging from 78.5 to 119.8 (MPa). A thorough examination of the fractured specimens revealed a brittle fracture mechanism, devoid of substantial plastic deformation. The onset of failures was frequently observed at the interface between the aluminum matrix and the steel mesh. The use of SEM and EDX investigations led to the confirmation of the uniformity of the copper coating and the absence of significant porosity or interfacial defects. A bimodal distribution of tensile strength values was observed, a phenomenon that is likely attributable to variations in mesh positioning and local differences in solidification. A correlation was established between the experimental results and an analytical polynomial model, thereby confirming a reasonable fit. In sum, the present study provides a substantial foundation for the development of metal matrix composites with enhanced performance, specifically designed for challenging structural applications. This method also demonstrates potential for recycling aluminum scrap into high-performance composites with controlled microstructure and mechanical integrity.}, language = {en} } @article{CojocaruTuriacFrunzaverdeetal.2024, author = {Cojocaru, Vasile and Turiac, Raul-Rusalin and Frunzaverde, Doina and Trisca, Gelu and Bacescu, Nicoleta and Marginean, Gabriela}, title = {Effect of the Printing Scenario on the Dimensional Accuracy and the Tensile Strength of Different Colored PLA Specimens Produced by Fused Deposition Modeling}, series = {Applied Sciences}, volume = {14 (2024)}, journal = {Applied Sciences}, number = {17, Artikel 7642}, doi = {10.3390/app14177642}, pages = {19 Seiten}, year = {2024}, abstract = {Dimensional accuracy and mechanical properties of components printed by fused deposition modeling (FDM) are influenced by several process parameters. In this paper, the authors targeted the effect of the printing scenario and the PLA (polylactic acid) color on parts' quality. Three scenarios were analyzed: individually printing, simultaneously printing of three, respective five specimens of natural (transparent), red, grey, and black PLA. The temperature variations of successive deposited layers were recorded for the black PLA. The dimensional accuracy of tensile specimens was evaluated, tensile tests were performed, and the results were correlated with the mesostructure of the prints. The effect of the independent variables on the measured parameters was analyzed by ANOVA. The experiments revealed differences for the same printing scenario regarding cross-section area (up to 5.71\%) and tensile strength (up to 10.45\%) determined by the material color. The number of specimens printed simultaneously and the position of the pecimens on the build plate were found to influence too, but less than the color. Thus, increasing from one to five the number of specimens printed at a time altered both the dimensional accuracy (up to 3.93\% increase of the cross-section area) and the tensile strength (up to 3.63\% reduction).}, language = {en} }