Aluminum Alloys, Characterization and Processing: Processing and Heat Treatment I
Sponsored by: TMS Light Metals Division, TMS: Aluminum Committee
Program Organizers: Julie Levesque, Quebec Metallurgy Center; Stephan Broek, Kensington Technology Inc
Monday 2:00 PM
March 20, 2023
Room: 32A
Location: SDCC
Session Chair: Mihaiela Isac, McGill Metals Processing Centre
2:00 PM
Comparison of TiB2 and TiC Grain Refiners’ Impact on Surface Quality, Edge Cracking, and Rolling Performance of AA5182 DC-Cast Ingot: Joshua Lawalin1; Pascal Gauthier2; Tao Wang2; 1Commonwealth Rolled Products; 2Rio Tinto Aluminum
Titanium diboride (TiB2) and titanium carbide (TiC) are both widely used as grain refiners in the production of DC-cast aluminum ingot for rolled products. This study evaluated industrially produced DC-cast aluminum ingot of alloy AA5182 with TiB2 and TiC and the grain refiners’ impact on ingot surface condition, as-cast microstructure, rolling performance, grain size distribution, as well as final product mechanical properties. Through optical microscopy and SEM-EDS metallographic examination of the sheet post-hot rolling, the study found that the use of TiC grain refiner resulted in fewer surface stress risers resulting in improved surface quality, rollability, and edge cracking performance of AA5182, as well as an improved grain size uniformity and less grain refiner agglomeration versus the same alloy cast with TiB2 grain refiner.
2:25 PM
The Influence of Crystallographic Texture Gradients on the Deformation Response of Aluminum Extrusions: Warren Poole1; Andrew Zang1; Yu Wang1; Mary Wells1; Nick Parson1; 1University of British Columbia
The use of 6xxx series aluminum extrusions in automotive applications is increasing due to the requirement to reduce vehicle weight. Extruded profiles can be subjected to severe and complex plastic strain paths during fabrication or during crash loading. During the extrusion process, deformation gradients develop due to i) friction between the tooling and the extrudate, ii) redundant work and iii) splitting of the extrusion and welding in porthole dies when fabricating hollow profiles. The current study examined these effects in materials with high dispersoid densities at relatively low extrusion temperatures (~400oC) where recrystallization was deliberately suppressed. Local textures were characterized using electron back scatter diffraction (EBSD) and the local stress-strain response was predicted using the visco-plastic self-consistent (VPSC) polycrystal plasticity model. The results were used to rationalize i) the inhomogeneity of through thickness deformation during tensile testing and ii) the localization of plastic deformation at the weld seam.
2:50 PM
Mechanical Properties and Microstructures of Cold Rolling Sheets of a Low-cost Continuous Cast Al-1.5Cu Alloy with Potential Application in Auto Sheets: Xiyu Wen1; Yan Jin1; Wei Li1; 1University of Kentucky
Mechanical properties, microstructures and textures of cold rolling sheet of a low-cost continuous casting (CC) Al-1.5Cu alloy by using tensile machine, optical & scanning electronic were evaluated and studied overall. Compared with AA5xxx and AA3xxx alloys, material characteristic after cold rolling at different gauges of the Al-Cu alloy is very different with some interesting findings because of the precipitation and re-solid resolution of AlCu phase. The findings from the cold rolling hardening would affect potentially and importantly subsequent processing (such as solid solution heat treatment, quenching, forming, and aging) for application (replace AA5xxx-O sheet) in auto sheets.
3:15 PM
Challenges in the Production of 5754 Automotive Alloy Sheet via Twin Roll Casting Route: Dionysios Spathis1; John Tsiros1; Andreas Mavroudis1; 1ELVAL SA
Industrial trial for the production of 5754 alloy automotive application sheets through the twin roll casting route was carried out in ELVAL’s rolling plant. The paper describes several challenges faced in order to produce final product within the automotive customer specs using the twin roll casting process. Microstructural control, as cast surface quality (level lines) and final mechanical properties are the major challenges in 5754 sheet production via twin roll casting. Microstructural control refers mainly in the final O temper grains size and the amount of the central line segregation phase. Casting two different 5754 alloy versions in respect to Mn content (High and low Mn alloy) and roll the coils to final gauge using the same thermomechanical process shows clearly the significant influence of alloy Mn content in the final grain size and in the final mechanical properties.
3:40 PM Break
3:55 PM
Fabrication of Bright-rolled Aluminum Suitable for Design Elements in the Automotive Industry: Anita Gruendlinger1; Peter Uggowitzer2; Josef Berneder1; 1AMAG rolling GmbH; 2ETH Zürich
The present work deals with the fabrication of rolled aluminum sheets based on 5xxx alloys, striving for a superior appearance and formability. Due to the material’s exceptional surface properties, processability and corrosion resistance the developed material may be employed to manufacture sophisticated design elements dedicated for the automotive industry. Beyond optical investigations conducted on brightened and anodized material, phase studies are carried out, suggesting thermal processing close to the solidus temperature prior to cold rolling. This is backed up by thermodynamic simulations, dealing with the impact of precipitates on the material’s appearance. Moreover, the grain structure as well as mechanical properties in temper H2X are tackled, addressing the demand for decorative elements with a sufficient formability and enhanced corrosion resistance.
4:20 PM
Effects of Aging Conditions on Fracture Characteristics of Al-Mg-Si Alloys: Zeynep Tutku Ozen1; Ilyas Artunc Sari1; Anil Umut Ozdemir1; Gorkem Ozcelik1; Abdullah Kagan Kinaci1; Alptug Tanses1; Emre Cankaya1; 1Asas Aluminyum As
Automotive industry has started using lightweight materials like aluminum with the aim of increasing fuel efficiency by supporting carbon neutral production. Structural parts of an automobile like bumper and chasis requires not only tensile strength but also crashworthiness. One of the main requirements of an aluminum alloy to increase crashworthiness by over aging of the alloys. In this study, 6005 aluminum alloy production has been followed with automotive parts production route of billet production by direct chill casting, homogenization, extrusion and heat treatment. Different natural and artificial aging conditions has been applied to 6005 alloy. Strengths, crashworthiness, elongations and fracture characteristics has been evaluated according to the results of characterization studies including tensile tests and SEM Analysis.
4:45 PM
Evaluation of EN AW 3003 Aluminium Alloy Homogenization with Specific Electrical Resistivity Measurement: Maja Voncina1; Mitja Petrič1; Sebastjan Kastelic1; Tilen Balaško1; Stanislav Kores2; Jožef Medved1; 1University of Ljubljana; 2Talum d.d.
The starting point of the research project was the control of the homogenization process of EN AW 3003 aluminium alloy. For this purpose, thermodynamic simulations of the studied alloy were carried out using the Thermo-Calc program to determine the temperature stability of the different phases and the equilibrium concentrations of these phases vs. temperature. Homogenization annealing was simulated using differential scanning calorimetry (DSC) and electrical resistance measurement to determine the suitability of such measurement for optimizing the homogenization process. The efficiency of the homogenization time was investigated using a standard homogenization process of the as-cast samples from the slab in the furnace, followed by a detailed microstructure analysis. Very good agreement was obtained between the simulation of homogenization with DSC analysis and the electrical resistivity curve, confirming the suitability of the electrical resistivity measurement method for monitoring the homogenization process of aluminium alloys.