Aluminum Alloys, Processing and Characterization: On-Demand Poster Session
Sponsored by: TMS Light Metals Division, TMS: Aluminum Committee
Program Organizers: Andre Phillion, McMaster University; Dmitry Eskin, Brunel University
Monday 8:00 AM
March 14, 2022
Room: Light Metals
Location: On-Demand Poster Hall
Interaction between Recrystallization and Second Phase Particles in Al-Mn Alloy with Impurities (Fe, Si): Kazuha Yamase1; Ken-ichi IKEDA1; Seiji Miura1; 1Hokkaido University
Impurities (Fe, Si) in Al-Mn alloys contribute to precipitates formation during thermal processing and introduction of large particle during solidification. Also, second phase particles affect recrystallization, e.g. “Particle Stimulated Nucleation (PSN)” and “Zener Pinning”. In this study, with various amount of impurities in Al-Mn alloy, we clarified the difference in morphology of second phase particles and in recrystallized structure.Low purity Al-1Mn alloy (2N-1Mn) and high purity Al-1Mn alloy (4N-1Mn) were hot-rolled and subsequently annealed at 300 °C, 400 °C, and 500 °C, respectively. SEM-EBSD and SEM-BSE observation revealed the following phenomena. In 2N-1Mn, recrystallization nucleation was found to be promoted by PSN, and Zener Pinning was strong due to fine precipitates. Namely, many recrystallized grains were present and remained small. In contrast, in 4N-1Mn, PSN was little because constituent particles were few, and precipitates were coarsened faster than 2N-1Mn. Therefore, the recrystallized grains overcame the Pinning and became large.
Development of High-strength 6xxx Aluminium Nanocomposites by Direct-chill Casting and Thermo-mechanical Processing: Guangyu Liu1; Mahfuz Karim1; Dmitry Eskin1; Brian McKay1; 1Brunel University London
Wrought aluminium alloys reinforced with ceramic particles have been extensively investigated for automotive applications due to their high specific strength. This study aims to push the limits of the strength of existing commercial high-strength 6xxx aluminium alloys (YS>340MPa) by incorporating ceramic reinforcing nanoparticles. Aluminium billets containing ~1wt% Al2O3 nanoparticles (<80 nm) are direct-chill cast and subsequently subjected to thermo-mechanical processing. Instead of adding loose Al2O3 nanoparticles directly to the melt, Al-20wt.%nanoAl2O3 alloys produced by high energy ball milling has been employed to aid their introduction. Stir mixing and ultrasonic processing techniques were applied to further enhance the dispersion of nanoparticles. The effect of the nanoparticles and the heat treatment on the microstructure with respect to casting defects, particles distributions and particle/matrix bonding have been thoroughly analysed. The microstructure and the mechanical properties of the thermo-mechanically processed composite billets are investigated in comparison with the benchmark alloys.
Effect of Minor Alloying Elements on Mechanical Properties of 6xxx Series Aluminum Alloy Sheets: Gyeongseok Joo1; MinSang Kim1; YongWook Song2; Hyunjoo Choi2; SeHoon Kim1; JaeHyuk Shin1; SoonMok Choi3; 1Korea Automotive Technology Institute; 2Kookmin University; 3Korea University of Technology & Education
Age hardenable Al-Mg-Si(-Cu) alloys have been widely used in automotive industries because of their good strength-ductility balance and excellent formability. The stregnth of these alloys can be greatly improved by nano-scale precipitates during againg, and previous work has mainly investigated the relation between these main strengthening precipiates and mechanical behavior of 6xxx series aluminum alloys. However, it has less been focused on the role of minor alloying elements on precipitate formation and mechanical behavior 6xxx series aluminum alloys.In this study, the precipitates and mechanical properties of 6xxx series aluminum alloys were analyzed by varying contents of additive alloying elements such as Mg, Si, Cu, Fe, and Mn. The phase of the alloys were quantitatively predicted by the phase analysis software, and the prediction results were compared with the microstructural analyses. The role of minor alloying elements on precipitate formation and mechanical behavior 6xxx series aluminum alloys will be discussed.
A Study on the Improvement of Plastic Deformability and Thermal Conductivity of High Strength Aluminum Alloy: Minsang Kim1; Gyeongseok Joo1; Hansol Son2; Hyunjoo Choi2; Sehoon Kim1; 1KATECH; 2Kookmin University
Electric vehicles (xEVs) have attracted a great deal of attention as a new mode of transportation because of their energy-efficient and environment-friendly features. These vehicles possess a number of electronic components or Li-ion batteries, which require special shielding materials to mechanically protect and thermally manage them. This study proposes Al-Si-Mg based alloys with high thermal conductivities as well as excellent mechanical properties. First, the effect of major alloying elements on phase formation in high strength cast/wrought aluminum alloys was investigated by comparing microstructural analysis and prediction by thermodynamics-based software. The relation between main precipitates and second phases and thermal conductivity/deformation behavior of the aluminum alloys will be discussed.
Fabricating Tubes with Variable Properties via Shear Assisted Processing and Extrusion: Mageshwari Komarasamy1; Scott Whalen1; Brandon Taysom1; Timothy Roosendaal1; Angel Ortiz1; Glenn Grant1; Darrell Herling1; 1Pacific Northwest National Laboratory
In a complex structural assembly, such as in automobiles and in aerospace structures, a single part will often need to perform more than one function. For example, B-pillar in automobiles should have high strength to sustain high dynamic loads and large elongation for increased energy absorption so that the combination will lead to increased crash resistance. In this study, shear assisted processing and extrusion (ShAPE) was utilized to create tubes with high strength/low ductility and high ductility/low strength regions in 6061 Al alloys. The ShAPE formed tubes were subjected to hardness and tensile property investigation in as-extruded and peak aged conditions. For instance, in peak aged condition, yield strength of 200+ MPa was noted in the highest strength region while >10% total elongation was noted in other regions. Additionally, various electron microscopy techniques were utilized to investigate the underlying microstructural features responsible for such property variation.