Discipline: Nanoscience or Materials Science
Subcategory: Materials Science
Session: 2
Room: Senate
Shyla M. Lugo Morán - University of Puerto Rico - Mayaguez
Aluminum alloys are of high interest due to their multifunctionality and properties such as strength, workability, and lightweight. In Al-Mg alloys, the Portevin-Le Chatelier (PLC) phenomenon manifests itself as serrations in the tensile stress vs. strain curve due to induced precipitation resulting from the interaction between moving dislocations and magnesium atoms supersaturating the Al solid solutions. Elemental components have been postulated by various theories describing the PLC phenomenon; however, an accurate model has not yet been developed. This research’s final goal is to evaluate the PLC phenomenon when Al2O3 nanoparticles are present in an Al-4.5%Mg matrix to diminish said phenomenon. The nanoparticles were obtained by fragmentation of 95% Al – 5% Al2O3 powder in a high-energy ball mill to produce nanocomposite pellets to facilitate the inoculation process during melting. X-ray diffraction and optical microscopy analyses showed that the cold-welding process between Al2O3 and Al was successful upon ball milling. Ongoing work includes the mechanical properties as a result of the nanoparticle’s addition to an Al-4.5%Mg alloy. To accomplish this, an Al – 4.5 wt.% Mg molten alloy will be cast with the nanocomposite pellets inoculated at 0.00, 0.25, 0.50, and 0.75 wt.%. Before the tensile test, the samples will go through a 30-minute solution treatment at 300° C, followed by water quenching. This project will contribute to the knowledge of the PLC phenomenon specifically regarding the use of nanoparticles to ameliorate the PLC effect, so as to improve the manufacturing of Al-Mg parts by cold work.
Funder Acknowledgement(s): My studies and research were funded by the E-PEARLS Scholarship and the CREST program facilities - NSF GRANT: 1906130.
Faculty Advisor: Oscar Marcelo Suárez, oscarmarcelo.suarez@upr.edu
Role: I did the fragmentation process of Al and Al2O3 in the high-energy ball mill to perform the cold-welding process. I did the analyses with X-ray diffraction and optical microscopy, cast the molten alloys with the nano-composite pellets, and heat treated them.