Magnesium Technology 2023: Poster Session
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
Monday 5:30 PM
March 20, 2023
Room: Exhibit Hall G
Location: SDCC
A Comparative Corrosion Study of Magnesium Alloys Processed via Shear Assisted Processing and Extrusion: Vikrant Beura1; Antriksh Sharma1; Vineet Joshi2; Kiran Solanki1; 1Arizona State University; 2Pacific Northwest National Laboratory
To understand the corrosion behavior due to changes in alloying composition, three separate magnesium alloys, namely Mg3Si, ZK60, and AZ31 were processed via the Shear Assisted Processing and Extrusion (ShAPE) technique. Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) based microstructure characterization revealed a refined microstructure with ShAPE processing in each alloy. A comparative corrosion response between cast and ShAPE processed alloys was studied by different electrochemical measurements such as potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), galvanostatic-potentiostatic cycle, and atomic emission spectroelectrochemistry analysis (AESCE). The extent and variation in dissolution-induced cathodic activation were found to vary with different alloy microstructures. To further understand the underlying mechanism, post-corrosion microstructures were analyzed with high-resolution microscopy and spectroscopy techniques. The result indicates that a particular processing method can have variation in corrosion response which depends strongly on alloying compositions, i.e., second phase particles and solute distribution of feedstock.
Cancelled
E-12: A Thermodynamic Approach for Precipitation Hardening of Magnesium Alloy with High Formability: Jong-Kwan Lee1; Hyo-Sun Jang2; Nack Joon Kim1; Byeong-Joo Lee1; 1POSTECH; 2Korea Institue of Materials Science
Non-basal slips play key roles to overcome the poor ductility and formability of magnesium. We have proposed that alloying elements can activate non-basal slips by reducing critical resolved shear stress anisotropy among slip systems, and the alloy with optimum composition for the non-basal slip activation shows high ductility and formability along with relatively low strength. Since magnesium alloy is a structural material, reasonable strength is required, and precipitation hardening is an effective way to improve the strength. Important here is that the additional alloying for precipitation hardening should not have a harmful effect on the optimized ductility and formability. In this presentation, it will be demonstrated how the thermodynamic calculation can be utilized to investigate the additional alloying and composition for precipitation hardening without disturbing the alloying elements for non-basal slip activation. The developed alloy shows remarkably improved strength without a significant decrease in ductility and formability.
E-13: Advanced In-situ Investigation of Deformation Behavior in a Textured Magnesium Alloy AZ31: Jan Dittrich1; Michal Knapek1; Daria Drozdenko1; Peter Minárik1; 1Charles University
A combination of mutually complementary in-situ experimental techniques, including electron backscatter diffraction (EBSD), acoustic emission (AE), and digital image correlation (DIC) was employed to study the geometry and dynamics of the deformation twinning band formation. The investigated material, a rolled magnesium alloy AZ31 exhibiting a strong basal texture, was uniaxially compressed in the rolling direction i.e., in a manner favorable to a pronounced activity of the extension twinning. The in-situ EBSD provided confirmation of the specific twin variant as well as an estimate of the twinned volume fraction evolution with progressing strain, whereas the DIC analysis coupled with the AE measurements revealed the macroscopic heterogeneities and provided insight into the dynamics of the twin band formation and propagation.
Advances in Magnesium Primary Production by Reactive Cathode Molten Salt Electrolysis with G-METS Distillation: Zujian Tang1; Keira Lynch1; Benjamin Perrin1; Armaghan Telgerafchi1; Gabriel Espinosa1; Daniel Sehar1; Madison Rutherford1; Adam Powell1; 1Worcester Polytechnic Institute
Molten salt electrolysis with a liquid tin or lead reactive cathode overcomes multiple challenges in reduction of magnesium oxide to metal, particularly the low density and high activity of magnesium metal. It can use carbon anodes in a design very similar to the Hall-Héroult cell, or solid oxide membrane (SOM) anodes for pure oxygen by-product production. G-METS distillation is potentially much more energy-efficient and lower cost than traditional batch distillation for separation of the magnesium metal product from the reactive cathode material. This talk will present new developments in this process. Electrolysis experiments with carbon and SOM anodes show outstanding current efficiency for both. An updated techno-economic analysis estimates capital and operating costs using both carbon and SOM anodes. Life cycle analysis of the process under three scenarios estimates the cradle-to-gate environmental impact. And a new thin-SOM anode design can improve scalability and energy efficiency.
E-14: Critical Resolved Shear Stresses for Slip and Twinning in Mg-Y-Ca Alloys and Their Effect on Ductility: Mingdi Yu1; Jingya Wang1; Xiaoqin Zeng1; Javier Llorca2; 1Shanghai Jiao Tong University; 2IMDEA Materials Institute & Technical University of Madrid
The deformation mechanisms in single crystals of a Mg-5Y-0.08Ca (wt. %) alloy along different orientations -selected to activate only one deformation mode- were studied by means of micropillar compression tests as well as slip trace analysis, transmission electron microscopy and transmission Kikuchi diffraction. It was found that the presence of Y and Ca led to a huge increase in the CRSS for <a> basal slip (29±5 MPa), <c+a> pyramidal slip (203±7 MPa) and tensile twin nucleation (above 148 MPa), while the CRSS for <a> prismatic slip only increases up to 105±4 MPa. The changes in the CRSS for slip and tensile twinning modify the dominant deformation mechanisms in polycrystals, leading to large improvements in ductility. In particular, tensile twinning is replaced by <a> prismatic slip during compressive deformation along the a axis and <a> prismatic slip is preferred to <c+a> pyramidal slip in grains suitable oriented for both.
Designing Highly Corrosion-resistant Mg Alloys via Second-phase Control: Sung Soo Park1; 1UNIST
Mg alloys are considered one of the most attractive structural materials for mobile goods such as personal vehicles and portable devices. However, industrially using Mg-based products in a variety of weight-sensitive components is still limited especially due to their poor corrosion resistance. It has been reported that the poor corrosion resistance is closely related with the occurrence of active microgalvanic corrosion between the Mg matrix and second-phase particles.Here, we report highly corrosion-resistant AZ-based Mg alloys whose corrosion resistance is equivalent to that of ultra-high-purity Mg, which is nearly free of the occurrence of microgalvanic corrosion in corrosive conditions. The excellent corrosion resistance appearing in the experimental Mg alloys is attributable to the reduced nobility of cathodic second-phase particles after controlled microalloying with rare-earth elements, resulting in significantly retarded microgalvanic corrosion in NaCl solution. Designing concept of the new Mg alloys and their automotive application trials will also be presented.
E-15: Effect of Differential Speed Rolling (DSR) on the Dynamic Recrystallization of Mg5Zn Under Different Temperatures: Christopher Hale1; 1North Carolina Agricultural and Technical State University
Magnesium-based alloys can be enhanced through a combination of annealing temperature and holding time prior to plastic deformation such as single-pass differential speed rolling (DSR) and conventional rolling (CR), where the material is strained and produces fine dynamic recrystallization (DRX) grains improving mechanical properties such as tensile strength and ductility. The magnesium (Mg)-based alloy under investigation in this study is Mg5Zn that is preheated to temperatures of 250 C, 300 °C, 350 C, and 400 C to analyze DSR and at 250 C and 350 C to analyze CR at various thickness reductions from 10% to 50% to understand the effect of single-pass DSR and CR on the dynamic recrystallization process of Mg5Zn and its influence on mechanical properties.
E-16: Effect of Grain Size on Bio-corrosion Properties of AZ31 Magnesium Alloy: Wenli Zhao1; Qizhen Li1; 1Washington State University
As a type of biodegradable material, AZ31 magnesium alloy has attracted many attentions in the bio-implanting field. Depending on the actual applications, it is often necessary to modify the microstructure of materials to achieve different properties. It is critical to understand the relationship between microstructure and corrosion property of AZ31 magnesium alloy. Grain size is the microstructural feature studied in this work. Heat treatment was employed to obtain the samples with different grain sizes. Bio-corrosion test was conducted for the samples through being immersed in simulated body fluid for various time intervals. Scanning electron microscope was employed for observing morphology changes due to corrosion testing. The results show that the corrosion rates increased with the immersion duration for the samples, the samples with larger grain size exhibited better corrosion resistance, and the corrosion mechanisms for the sample was uniformly pitting corrosion.
Effect of Second Phases Evolved Through Heat Treatment on Mechanical and Bio-corrosion Behaviour of a Mg-Zn-Ca-Mn Alloy: Darothi Bairagi1; Sumantra Mandal1; Manas Paliwal1; 1IIT Kharagpur
Although the Mg-based alloys hold an enormous potential to be used for temporary implants, their widespread application is still restricted due to their rapid degradation rate in body fluid. Towards this, a novel Mg-Zn-Ca-Mn alloy has been developed where each of the alloying element is body nutrient element and thus ensure biosafety. A heat treatment schedule has been designed for the alloy based on thermodynamic and kinetic modelling (by FactSage software using FTlite database) to ensure optimum homogenization of the solute elements. Through experimentation, it has been observed that the parameters chosen for heat treatment through modelling fetches sufficient mechanical properties for temporary fixture applications. Moreover, the influence of optimized homogenization parameters towards the improvement on in-vitro bio-corrosion property of the alloy has been systematically studied.
E-17: European Sustainable Magnesium from Chromite Production and Dolomite Excavation Residues: Duane Runciman1; Matt Dey1; Henk van der Laan2; Carsten Dittrich3; Edward Peters3; Thore Perlitz3; Blaz Likozar4; Alen Rupnik4; Konstantinos Sakkas4; Beate Orberger5; 1Mures SRL; 2V.I.C. Van der Laan International Consultancy BV; 3MEAB Chemietechnik GmbH; 4National Institute of Chemistry of Slovenia; 5CATURA Geoprojects
The recently funded EIT EU Magnesium project seeks to contribute to the first domestic Magnesium production in Europe. At present, Europe fully depends on Chinese imports. Last year there was an enormous Mg supply disruption because of an electricity shortage in China. The European aluminium industry was dramatically affected by the Mg supply disruption and corresponding price spike. The magnesium price reached a record of US $ 12.000 /mt up from US $ 2.000 /mt earlier in the year. In the Mures County in North-central Romania, 1.94 million tonnes of chromium ore process residues (COPR) are available as Mg, but also as additional Cr and CaCl2 and NaOH resource. Mures SRL will construct the plant on its 84-ha property to produce mainly Mg metal and other by-products. Hydrometallurgical ecological processing will be used to recover not only Mg but the hazardous Cr6+ which will be recovered as Cr2O3 rendering this process environmentally friendly. In addition, the process will incorporate a mixed salt electrolytic unit to convert MgCl2 to Mg metal which is a low carbon footprint route in comparison to the conventional Pidgeon process employed mainly in China. With a ca. 19,000 tpy of Mg metal capacity in phase 1 of operation (2026 – 2034), Mures will contribute13.5% of the EU Mg demand during the first 9 years. In phase 2 (beyond 2034), micronized dolomite will be used as the feed material and the capacity will be increased to 25,000 tpy Mg equivalent to 15% of EU demand.
E-18: Flammability Resistant Magnesium Alloys Processed by Equal Channel Angular Pressing: Stanislav Sasek1; Jitka Stráská1; Peter Minárik1; Robert Král1; Jozef Veselý1; Jiří Kubásek2; 1Charles University; 2University of Chemistry and Technology
Two magnesium alloys (Mg-2Y-2Gd-1Ca, Mg-2Y-2Nd-1Ca) were designed with an emphasis on high flammability resistance while maintaining solid mechanical properties. Both alloys were processed by equal channel angular pressing (ECAP) to achieve finer microstructure and enhanced strength. Both alloys are characterized by exceptional high ignition temperature caused by a structurally stable oxide layer. Processing by ECAP led to a homogenous ultrafine-grained microstructure with mean grain size ~ 1 µm. TEM analysis revealed uniform distribution of submicrometer secondary phases particles. Deformation tests and microhardness measurement proved that developed and analysed microstructural condition resulted in solid mechanical properties with yield strength exceeding 250 MPa in tension and compression. However, the segregation of calcium at the grain boundaries led to a significant reduction in ductility.
E-19: Formation of CO2 Absorption Induced Corrosion Resistant Magnesium Carbonate Layer Formation on Various Magnesium Alloys: Gyoung Gug Jang1; Jiheon Jun1; Yi-Feng Su1; 1Oak Ridge National Lab
We demonstrated that intermediate thermal CO2 treatment forms a highly corrosion-resistant magnesium carbonate layer on two Mg alloys (i.e., AM60 and AZ91D) via molten salt facilitated CO2 absorption to MgO layer. The corrosion mitigation performance from this treatment for each alloy was fully evaluated by electrochemical measurements and hydrogen collection using flat and curved surface specimens. Particularly, a dip coating applied on Mg alloy samples with curved surfaces and holes, to demonstrate the feasibility of this treatment to achieve corrosion resistance of Mg alloy parts with more complex geometries. CO2 thermal treated Mg alloy specimens exhibited the long-term corrosion resistance, compared to the untreated specimens. High resolution microscopic analysis and XRD measurement were employed to investigate the chemical composition of carbonate layer and define the formation mechanism. The results from SEM, TEM-EDS, STEM-EELS and XRD indicated that the porous MgO was reconstructed to a dense and protective Mg-O-C-Li layer.
E-20: In Vitro and In Vivo Degradation Behavior of Novel Corrosion-resistant Mg Alloys: Du-Won Min1; Jung Gu Lee2; Sung Soo Park1; 1UNIST; 2University of Ulsan
Of various metallic elements, Mg is considered one of the most feasible biodegradable materials since it can be excreted in the urine after degradation in the body. However, commercially available Mg and its alloys generally suffer from more rapid and localized degradation than other biodegradable materials in an aqueous environment containing salts like seawater or blood, resulting in their premature decay after implantation. Furthermore, H2 gas bubbles generating during rapid degradation of Mg can cause inflammation by creating cavities on the tissue. Here, as an alternative to the conventionally available Mg-based materials, the authors suggest a new type of Mg alloy with highly enhanced corrosion resistance, giving expectations to exclude the active biodegradation after its implantation. In this study, in vitro and in vivo biodegradation behavior of the experimental and commercial Mg alloys was comparatively investigated to see the possibility of the new material in future biodegradable implant applications.
E-21: Investigating the Corrosion Response of Cast and Extruded ZK60 Magnesium Alloy Processed via Shear Assisted Processing and Extrusion: Vikrant Beura1; Antriksh Sharma1; Vineet Joshi2; Kiran Solanki1; 1Arizona State University; 2Pacific Northwest National Laboratory
An increase in demand for high-strength and corrosion-resistant magnesium alloys in transportation sectors has driven the development of new processing techniques. Towards this, in this work, cast and extruded ZK60 magnesium alloys were processed using a novel solid-state process i.e., Shear Assisted Processing and Extrusion (ShAPE). Processing-induced microstructure were characterized using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) techniques, which revealed an extensive refinement in grain size, distribution of solutes (Zn and Zr) and second phases, and overall texture. Comparative corrosion analysis of ShAPE and feedstock alloys was performed using various electrochemical measurements such as potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and atomic emission spectroelectrochemistry analysis (AESCE) that indicate an improvement in corrosion resistance with ShAPE processing for cast feedstock but not for extruded ZK60. Post-corrosion microstructures were analyzed to elucidate the underlying corrosion mechanism.
E-22: Investigation of Transformation-mediated Nanotwin Nucleation Mechanisms in Magnesium Using Deep Neural Network Interatomic Potentials: Mehrab Lotfpour1; Iyyappa Rajan1; Amir Hassan Zahiri1; Jamie Ombogo1; Lei Cao1; 1University of Nevada
Recently we reported the discovery of a rigorous nucleation mechanism for {101 ̅2} twins in hexagonal close-packed (hcp) magnesium through reversible hcp-tetragonal-hcp martensitic phase transformations. The evanescent nature of the intermediate tetragonal phase hinders its direct observation via experiments, so molecular dynamics simulation served as a unique tool in these studies. However, conventional interatomic potentials suffer notable inaccuracies, so we have developed a high-accuracy deep neural network interatomic potential using ab initio molecular dynamics data. The results were compared with those from molecular dynamics simulations using conventional embedded atom method potentials. Specifically, we confirmed that extensive twinning processes follow the transformation-mediated twinning mechanism and follow strict orientation relations between the parent hcp phase, intermediate phase, and twin hcp phases. This work will be important for a better understanding of the twinning mechanism and thus the development of novel strategies for enhancing the ductility of magnesium alloys.
E-23: Kink Bands Strengthening of LPSO Mg-Zn-Y alloys After Processing by High-pressure Sliding (HPS): Yongpeng Tang1; Shinichi Inoue2; Yoshihito Kawamura2; Zenji Horita2; 1Kyushu Institute of Technology; 2Kumamoto University
The kink-band strengthening effect was investigated using a single crystalline long periodic stacking ordered (LPSO) Mg85Zn6Y9 alloy after processing by high-pressure sliding (HPS). The strain introduced by the HPS process was correlated with the microhardness and the kink-band formation. The enhanced strength due to induced kink bands were quantitatively investigated associated with the equivalent strain. Compression tests together with microstructural observations showed that the strengthening of the alloy including ductility depends on the direction of kink boundaries.
E-24: Nucleation of {1012} Twins in Magnesium Through Reversible Martensitic Phase Transformation: Jamie Ombogo1; Amir Hassan Zahiri1; Lei Cao1; 1University of Nevada
We report the discovery of a rigorous nucleation mechanism for {101Ż2} twins in hexagonal close-packed (hcp) magnesium through reversible hcp-tetragonal-hcp martensitic phase transformations with a metastable tetragonal phase as the intermediate state. Specifically, the parent hcp phase first transforms to a metastable tetragonal phase, which subsequently transforms to a twinned hcp phase. The evanescent nature of the tetragonal phase severely hinders its direct observation, while our carefully designed molecular dynamics simulations rigorously reveal the critical role of this metastable phase in the nucleation of {101Ż2} twins in magnesium. Moreover, we prove that the reversible hcp-tetragonal-hcp phase transformations involved in the twinning process follow strict orientation relations between the parent hcp, intermediate tetragonal, and twin hcp phases. This phase transformation-mediated twinning mechanism is naturally compatible with the ultrafast twin growth speed.
E-25: Simulations of Microgalvanic Effects in Corrosion of Mg Alloys: Vishwas Goel1; Yanjun Lyu1; David Montiel1; Katsuyo Thornton1; 1University of Michigan
We employed a phase-field model implemented within the PRISMS-PF framework to investigate corrosion in Mg alloys. When the corrosion rate was limited by the cathodic reaction, an increase in cathodic-phase fraction led to a higher corrosion rate due to an increase in the cathodic-phase/electrolyte interfacial area. Additionally, we observed an acceleration in corrosion as the anodic phase corroded and exposed more of the cathodic phase to the electrolyte. The distribution of the corrosion current, as well as the morphology of the corroded surface, infer an existence of two length scales, one that is small and is associated with a larger corrosion current near the triple phase boundary, and the other on a larger scale, greater than the simulation domain size we examined. The study was conducted in two- and three-dimensions, both of which exhibited similar corrosion behavior.
E-26: Strain Rate Dependent Deformation Behavior and Microstructure Evolution of Magnesium Alloys: Xinyu Xu1; Yizhuang Li1; Chengpeng Huang1; MingXin Huang1; 1The University of Hong Kong
Magnesium (Mg) alloys have received tremendous attention over the last few decades for improving energy efficiency of various engineering fields. To achieve widespread applications, understanding the dynamic mechanical response of the Mg alloys at different strain rates becomes a crucial issue for judging their in-service performance. In the present work, the mechanical properties of the Mg alloys were investigated at moderate strain rates and high strain rates, respectively. Microstructure evolution was characterized by the in-situ EBSD technique and the dislocation density, including the fractions of dislocations with different Burgers vectors, was determined based on the synchrotron XRD data. The rate sensitivity of plastic deformation was studied. A different deformation mechanism at high strain rate is observed and possible mechanisms contributing to this effect are explored.
E-27: Strain-localized Deformation Banding during Tensile Deformation of Pre-compressed AZ31 Mg Alloy: Jongbin Go1; Myeong-heom Park1; Si Gao1; Nobuhiro Tsuji1; 1Kyoto University
Deformation twinning and detwinning are important deformation mechanisms in addition to the basal <a> slip in HCP Mg alloys. It has been reported that deformation twinning or detwinning in Mg alloys can cause macroscopic inhomogeneous deformation. However, the effect of detwinning on the deformation behavior in Mg alloys has been much less reported. In this study, a hot-rolled and annealed AZ31 (Mg-3Al-0.5Zn-0.3Mn, wt.%) plate with a strong {0002}//ND (normal direction) texture was compressed along the transverse direction (TD) to have ~50% area fraction of deformation twins, and then subjected to tensile test combined with digital image correlation (DIC). The DIC analysis revealed that strain-localized deformation bands repeatedly formed, propagated and disappeared in the gage part of the specimens during tensile deformation, which has not been reported before. Microstructural changes corresponding to such deformation banding were characterized by SEM-EBSD and other techniques, and underlying mechanisms of the deformation banding are discussed.
E-28: Towards Improved Understanding of Press and Sinter Processing of Mg and Mg Alloy Powders: Steven Johnson1; William Caron1; 1Central Connecticut State University
Near shape forming of magnesium (Mg) alloy powders offers significant opportunity for structural material light weighting. Work to date indicates Mg/Mg alloy powders can be consolidated using conventional press and sinter processing to some extent. While reasonably compressible, densification of Mg/Mg alloy powders using solid and liquid state sintering is challenging. The presence of adsorbed O2 containing compounds and/or absorbed powder particle surface oxide layers most likely impedes solid and liquid state interparticle sintering. Results presented here attempt to analyze and experimentally progress sintering of consolidated Mg/Mg alloy powders. Thermal desorption results are presented qualitatively identifying powder particle adsorbed O2 containing compounds. Additionally, results of the effect of sintering Mg/Mg alloy powders in totally O2 (g) free inert atmospheres are presented. Sintered powder compacts are generally characterized for density, phase development, microstructure, and microstructure composition. Results of this work are intended to enhance the understanding of sintering Mg/Mg alloy powders.
E-29: Understanding the Influence of Alloying on Texture Development in Mg-(Zn-Ca) Alloys During Recrystallization: Rogine Gomez1; Aeriel Leonard1; 1The Ohio State University
Magnesium and its alloys have seen an increase in research interest due to its lightweight properties and potential for transportation applications. However, its hexagonal close packed structure and strong basal texture result in anisotropy and low temperature formability, which hinders its expansion for further usage. It has been found that alloying with Ca and Zn reduces the strong basal crystallographic texture formed during wrought processing. In this study, the texture evolution of Mg-(Ca,Zn) alloys was investigated during recrystallization at temperatures ranging from 200°C to 350°C for various times. SEM-EBSD was used to quantify the recrystallization fraction as well as determine preferential nucleation sites throughout the microstructure. In-situ heating was combined with SEM to understand the texture of recrystallized grains from preferential nucleation sites and the influence of crystallographic orientation on grain growth. It was determined that binary alloys develop a strong basal texture during wrought processing that weakens during recrystallization.