Magnesium Technology: Fundamentals of Plastic Deformation and Primary Production, Recycling and Ecological Issues
Sponsored by: TMS Light Metals Division, TMS: Magnesium Committee
Program Organizers: Petra Maier, University of Applied Sciences Stralsund; Steven Barela, Terves, Inc; Victoria Miller, University of Florida; Neale Neelameggham, IND LLC
Tuesday 8:00 AM
March 1, 2022
Room: 210A
Location: Anaheim Convention Center
Session Chair: Tracy Berman, University of Michigan; Dmytro Orlov, Lund University; Joshua Caris, Terves, Llc.; Aaron Palumbo, Big Blue Technologies
8:00 AM Invited
Strengthening Mechanisms and Thermal Stability of MgLiCa Alloys Processed by Severe Plastic Deformation: Heather Salvador1; Suveen Mathaudhu1; 1University of California-Riverside
Magnesium-Lithium alloys have long been investigated for their potential to realized ultralightweight structural materials, however efforts have been limited by a combination of low strength and thermal stability at low homologous temperatures. We report the implementation of severe plastic deformation (specifically, high-pressure torsion (HPT)) to refine the grains structures of Mg-3.5Li-0.6Ca (wt%) alloy to the sub-micrometer regime via the imposition of variable hydrostatic pressure and strain. The grain refinement results in increased hardness and strength while Mg2Ca nanoprecipitates further strengthen the alloy and hinder grain boundary movement at elevated temperatures. Recrystallization curves as a function of strain applied during HPT with concurrent microstructural and strength/hardness evolution are reported and compared with literature reports of deformation processed MgLi alloys.
8:20 AM
A Magnesium Clean Energy Ecosystem Vision: Adam Powell1; 1Worcester Polytechnic Institute
Magnesium is an abundant and energy-dense metal. A new distillation technology called Gravity-Assisted Multiple Effect Thermal System (G-METS) could enable its use in multiple technologies for recycling and CO2 drawdown. In addition to magnesium alloy recycling, G-METS can enable low-cost magnesium oxide reduction in a reactive tin cathode Hall-Héroult cell – but up to 33% more productive than for aluminum due to the lower valence of magnesium. It can reduce the energy use of liquid magnesium leaching for rare earth magnet recycling by up to 70%, and cut the cost in half. A molten salt magnesium-air battery can convert magnesium metal to electricity at up to 80% efficiency. And magnesium hydride slurry in a light hydrocarbon is a zero GHG emissions aviation fuel, whose MgO nanoparticle exhaust absorbs CO2 from the atmosphere as dilute MgCO3 or Mg(HCO3)2 rain, with calculated aircraft range longer than for plain hydrocarbons.
8:40 AM
ILTEC Technology in Magnesium Industry – Elimination of Water as Cooling Medium: Andreas Filzwieser1; Hans-Jörg Krassnig1; Martina Hanel1; 1METTOP GmbH
In the continuous casting of magnesium, still the use of water for cooling is common practice, which is a severe risk in the event of a malfunction. The ILTEC Technology with the ionic liquid IL-B2001 as a cooling medium can provide a remedy, because of the non-explosive reactions but efficient cooling properties. Proven in tests by pumping the ionic liquid in molten magnesium and supported by long years’ experience of cooling applications all over in the non-ferrous as well as iron and steel industry, ILTEC can provide a more safe casting for operators as well as the equipment. The paper is intended to describe the ILTEC Technology and to answer FAQs, with the special focus of implementation of the safe and water free technology in the magnesium industry.
9:00 AM
Design of Efficient Low-cost Recycling of Magnesium Using Gravity-driven Multiple Effect Thermal System (G-METS): Gabriel Espinosa1; Armaghan Telgerafchi1; Daniel McArthur1; Madison Rutherford1; Adam Powell1; David Dussault2; 1Worcester Polytechnic Institute; 2Elemental Beverage Company
The process of multiple effect distillation for the recycling of magnesium can both increase efficiency and reduce cost by up to 90% when compared to batch distillation refinement. This paper will detail the design and experimentation of a novel continuous gravity-driven multiple effect thermal system (G-METS) distillation process for magnesium alloys. Single-effect batch distiller experiments examine the evaporation kinetics of Mg alloys while confirming aerosol separation techniques. Further experiments using a two-effect, and later three-effect, continuous G-METS distiller seek to validate model predictions and magnesium recovery rates. Magnesium alloy recycling via distillation presents unique challenges that require various design considerations, such as temperature differentials and counter-flow processes for volatile element separation. The described application of G-METS for recycling offers an opportunity for low-cost recovery of pure magnesium from multiple types of magnesium-based alloys.
9:20 AM
Mg-Ca-X Alloys – A Brief Fact Sheet of High Strength Mg Wrought Alloys: Nikolaus Papenberg1; Clemens Simson1; Stefan Gneiger1; 1Light Metals Technologies Ranshofen
Mg alloys are often regarded as remarkable lightweight structural materials for both cast and wrought applications, enabling parts with low mass andgood specific mechanical properties. Nevertheless, in the case of highest strength requirements, no industrial satisfactory solution using Mg alloys has been found yet. While Mg alloys containing considerable amounts of rare earth elements are known to reach high strength levels, the material costs and availability are a hindrance for widespread application. Alloys based on the Mg-Ca-X system on the other hand, provide high strength and adequate ductility using abundant alloying elements. These materials can therefore be considered frontrunners for a new generation of high strength Mg wrought alloys. An introduction to the alloying and production principles of Mg-Ca-X alloys will be given and potential variants presented.