2020 Technical Division Student Poster Contest: LMD 2020 Technical Division Undergraduate Student Poster Contest
Sponsored by: TMS Extraction and Processing Division, TMS Functional Materials Division, TMS Light Metals Division, TMS Materials Processing and Manufacturing Division, TMS Structural Materials Division
Program Organizers: TMS Administration
Monday 5:30 PM
February 24, 2020
Room: Sails Pavilion
Location: San Diego Convention Ctr
SPU-7: Corrosion Study on the Al-Ce Eutectic Alloys in NaOH and HCl Aqueous Solutions: Kenneth Silva-Reyes1; Oscar Suarez1; 1University of Puerto Rico, Mayaguez
This research is focused on studying the corrosion behavior of Al-Ce alloy. The specimens underwent corrosion at different concentrations of NaOH and HCl aqueous solutions. To analyze such corrosion behavior, this research attempted to assess the mechanism that governs the process as it evaluates the effect on the surface microstructure. The parent alloy was prepared using pure aluminum and an Al-16wt.%Ce master alloy, melted at 760°C, and cast into a pre-heated copper mold. A water-cooled copper slab was placed over the melt and submerged into chilled water to attain fast solidification and to refine the microstructure. Then, the samples underwent corrosion at different times and concentrations of NaOH and HCl aqueous solutions. They were then characterized by optical-microscopy, x-ray diffraction, and electrochemical measurements. Preliminary results revealed changes in the open-circuit potential and the corroded alloy microstructure.
SPU-8: Effect of Thermomagnetic Processing on the Properties and Microstructure of Aluminum Alloys: Michael Thompson1; David Weiss2; Bart Murphy3; Hunter Henderson3; Orlando Rios3; Gerard Ludtka3; Aurelien Perron4; Michael Kesler3; 1The University of Tennessee; 2Eck Industries; 3Oak Ridge National Laboratory; 4Lawrence Livermore National Laboratory
Processing materials under magnetic fields is an underexplored technique to improve structure and mechanical properties in metals and alloys. Magnetic fields can alter phase stability, modify diffusion characteristics, and alter material flow substantially. In castings, magnetic fields can be used during melting of the alloy, during solidification, or during post-processing operations such as heat treatment to achieve structural changes. This work investigates the effectiveness of thermomagnetic processing during heat treatment of Al alloys containing in the Al-Cu, Al-Si-Cu, and Al-Mg-Ce systems. We demonstrate an improvement in mechanical properties and a reduction in required heat treatment times for all alloys.
SPU-9: Effects of Mg+Si Additions on the Microstructure and Mechanical Properties of Al-Ce-Sr based Alloys: Ramon Padin1; Manny de Jesus1; Oscar Marcelo Suarez1; 1University of Puerto Rico at Mayaguez
This project aims to study the effects of minute additions of Mg and Si to produce a creep resistant and competitive Al-Ce-Sr alloy. To these purposes, alloys with high concentrations of Ce and Sr with minute additions of Mg and Si in a 5:1 atomic ratio were arc melted in an argon atmosphere. A twofold increase in hardness at a maximum concentration of 5.9% wt. Mg and 1.3% wt. Si resulted with no significant change in hardness after T4 or T6 heat treatment. Optical microscopy and Vickers hardness tests permitted to evaluate the microstructure and mechanical properties, respectively. X-ray diffraction allowed identifying the phases present before and after heat treatment. Ancillary density measurements revealed a 3.6% decrease in density at the highest Mg and Si content. Ongoing work involves SEM and EDS for phase identification and chemical composition determination.