Magnesium Technology 2023: Primary Production and Recycling / Alloy Development
Sponsored by: TMS Light Metals Division, TMS: Magnesium Committee
Program Organizers: Steven Barela, Terves, Inc; Aeriel Murphy-Leonard, Ohio State University; Petra Maier, University of Applied Sciences Stralsund; Neale Neelameggham, IND LLC; Suveen Mathaudhu, Colorado School of Mines; Victoria Miller, University of Florida

Wednesday 8:30 AM
March 22, 2023
Room: 30C
Location: SDCC

Session Chair: Aaron Palumbo, Big Blue Technologies

8:30 AM
Design of the Continuous Gravity-driven Multiple Effect Thermal System (G-METS) for Efficient Low-cost Magnesium Recycling: Daniel Mc Arthur Sehar¹; Adam Powell¹; Armaghan Telgerafchi¹; Chinenye Chinwego¹; Gabriel Espinosa¹; Keira Lynch¹; Benjamin Perrin¹; ¹Worcester Polytechnic Institute
    An increase in the demand for structural materials has improved considerably from the past few years with the properties of low-density has impelled to the improvement of lightweight and energy efficient materials. The magnesium metal is used in several lightweight transportation applications because of its beneficial low density with outstanding stiffness and high strength to weight ratios. A new method for recycling of magnesium is multiple effect distillation which can substantially increase the efficiency of the system and thereby reducing the overall cost up to 90% when compared to the conventional batch method distillation. This G-METS distillation is a continuous operation which assists in recovering the pure magnesium metal from several magnesium-based alloys. This study showcases the design of continuous G-METS distillation of magnesium alloys considering the experimental data of the distiller to substantiate model estimates and effective magnesium recovery rates.

8:50 AM  Invited
Development of Compound-vertical-retort Technology for Magnesium Production and its Application: Fengqin Liu¹; Shaojun Zhang²; Rongbin Li¹; Peixu Yang²; Jinhui Liu²; Michael Ren³; ¹University of Science and Technology Beijing; ²Zhengzhou University; ³Sunlightmetal Consulting Inc.
    This paper introduces a new silicothermic process, compound-vertical-retort technology for magnesium production. It solves problems such as low mechanization, low productivity, short retort service life, high heat-resistant steel consumption, low magnesium yield, adhesion and glaze, poor furnace temperature uniformity, large heat losses, high carbon emissions and poor working environment, etc. A 1200 t/a Demonstration Plant has been built to demonstrate this technology. Ceramic-lined steel retort solved the problem of ‘adhesion and glaze’, with mechanical slag releasing; 99.8% Magnesium metal purity has been achieved via new compound magnesium crystallizer with radiation heating surface and sectional crystallization. Waste heat is recovered by a boiler for high-temperature slag for further saving energy and decreasing the CO2 emission. New dual-regenerative furnace was developed to realize temperature uniformity, to further improve combustion efficiency and heat efficiency. this new technology’s economic and technical indices are significantly better than that of the Pidgeon process.

9:10 AM
Development of Magnesium-Strontium / Calcium (Mg-Sr/Ca) Based Alloys with Improved Sinterability for Next Generation Biomedical Implants: Mert Celikin¹; Ava Azadi¹; Hyeonseok Kim¹; Ted Vaughan²; Eoin O'Cearbhaill¹; ¹University College Dublin; ²University of Galway
    The use of biodegradable alloys for bone fixation devices have potential to improve patients’ quality of life by avoiding the necessary secondary operations conducted regularly for the removal of implants fabricated from conventional non-resorbable alloys. Mg-alloys have excellent biocompatibility and biodegradability along with low modulus of elasticity which will decrease bone-shielding effects. However, low corrosion resistance and relatively poor mechanical performance limit their use for biomedical applications. This study focuses on the processing of novel Mg-Sr based alloys via powder metallurgical route. Thermodynamic calculations are used to predict the liquid phase fractions in order to control sinterability and porosity levels without compensating structural integrity. Materials characterisation was conducted to validate the thermodynamic modelling results using optical and scanning electron microscopy (SEM/EDS) as well as X-ray Diffraction (XRD). Final porosity levels were determined using X-ray Computed Tomography (CT). Mechanical performance was evaluated in comparison to cast alloys via compression testing.

9:30 AM
Development of Mg-based Superelastic Alloy through Aging Heat Treatment: Keisuke Yamagishi¹; Yukiko Ogawa²; Daisuke Ando¹; Yuji Sutou¹; ¹Tohoku University; ²National Institute for Materials Science
    In 2016, we found and reported a Mg-20.5 at.% Sc alloy shows superelasticity. The working temperature was, however, too low (-150慢) for the alloy to be put into practical use. Since the phase stability of the matrix bcc phase and the martensite phase largely depends on Sc content, we controlled it and recently realized superelasticity even at room temperature in a Mg-18.8 at.% Sc alloy. The obtained superelastic strain was, however, just 0.7% which is much smaller than that in practical superelastic alloy, Ni-Ti (6-8%). In my presentation, I will present our recent work especially on the effect of aging heat treatment on martensitic transformation and room temperature superelasticity in Mg-Sc alloy.

9:50 AM
Processing Map and Performance of a Low-cost Wrought Mg Alloy: ZAXEM11100: Thomas Avey¹; Josh Caris²; Jiashi Miao¹; Anil Sachdev³; Alan Luo¹; ¹Ohio State University; ²Terves Inc; ³General Motors
    Lightweight components improve the fuel efficiency in internal combustion vehicles and compensate for the battery weight and extend the drive range in electrified vehicles. Many Mg alloys have been developed over the years to meet these demands, however, low formability at room temperature, corrosion, and high cost have inhibited widespread adoption in the automotive industry. The new alloy Mg-1Zn-1Al-0.5Ca-0.2Ce-0.4Mn (ZAXEM 11100, all in weight %) has shown excellent post-rolling formability with an Ericksen Index of 7.8 mm and a post-T6 yield stress of 270 MPa in lab-scale sheet samples of 1mm thickness. In this work, a processing map has been developed for the new alloy, based on Gleeble thermomechanical test. This processing map provided important guidance to a production-scale extrusion. This work details the mechanical performance of ZAXEM11100 as an extrusion alloy.