Magnesium Technology

2011 Proceedings of a symposium sponsored by the

Magnesium Committee of the Light Metals Division of The Minerals, Metals & Materials Society (TMS)

Held during TMS 2011 Annual Meeting & Exhibition

San Diego, California, USA February 27-March 3, 2011

Edited by

Wim H. Sillekens Sean R. Agnew

Neale R. Neelameggham Suveen N. Mathaudhu

WILEY TIMS A John Wiley & Sons, Inc., Publication

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Magnesium Technology

2011

Check out these new proceeding volumes from the TMS 2011 Annual Meeting, available from publisher John Wiley & Sons:

2nd International Symposium on High-Temperature Metallurgical Processing

Energy Technology 2011 : Carbon Dioxide and Other Greenhouse Gas Reduction Metallurgy and Waste Heat Recovery

EPD Congress 2011

Friction Stir Welding and Processing VI

Light Metals 2011

Magnesium Technology 2011

Recycling of Electronic Waste II, Proceedings of the Second Symposium

Sensors, Sampling and Simulation for Process Control

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TMS2011140th Annual Meeting & Exhibition

Magnesium Technology

2011 Proceedings of a symposium sponsored by the

Magnesium Committee of the Light Metals Division of The Minerals, Metals & Materials Society (TMS)

Held during TMS 2011 Annual Meeting & Exhibition

San Diego, California, USA February 27-March 3, 2011

Edited by

Wim H. Sillekens Sean R. Agnew

Neale R. Neelameggham Suveen N. Mathaudhu

WILEY TIMS A John Wiley & Sons, Inc., Publication

Copyright © 2011 by The Minerals, Metals, & Materials Society. All rights reserved.

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WILEY TIMS A John Wiley & Sons, Inc., Publication

TABLE OF CONTENTS Magnesium Technology 2011

Preface xi About the Editor xiv About the Organizers xiv

Magnesium Technology 2011

Opening Session

Magnesium in North America: A Changing Landscape 3 S. Slade

Global Magnesium Research: State-of-the-Art and What's Next? 5 K. Kainer

Environmental Challenges for the Magnesium Industry 7 R. Brown

Predicting Mg Strength from First-principles: Solid-solution Strengthening, Softening, and Cross-slip 13 D. Trinkle, J. Yasi, andL. Hector

Biodegradable Magnesium Implants - How Do They Corrode in-vivo? 17 F. Witte, N. Hort, and F. Feyerabend

The Next Generation of Magnesium Based Material to Sustain the Intergovernmental Panel on Climate Change Policy 19

F. D'Errico, G Garces, and S. Fare

JIM INTERNATIONAL SCHOLAR AWARD WINNER: Fracture Mechanism and Toughness in Fine- and Coarse-Grained Magnesium Alloys 25

H. Somekawa, A. Singh, and T. Mukai

Primary Production; Characterization and Mechanical Performance

The Development of the Multipolar Magnesium Cell: A Case History of International Cooperation in a Competitive World 31

O. Sivilotti

Effect of KC1 on Liquidus of LiF-MgF2 Molten Salts 35 S. Yang, F. Yang, X. Hu, Z. Wang, Z. Shi, andB. Gao

Efficiency and Stability of Solid Oxide Membrane Electrolyzers for Magnesium Production 39 E. Gratz, S. Pati, J. Milshtein, A. Powell, and U. Pal

Magnesium Production by Vacuum Aluminothemic Reduction of A Mixture of Calcined Dolomite and Calcined Magnesite 43

W. Hu, N. Feng, Y. Wang, and Z. Wang

Multiphase Diffusion Study for Mg-Al Binary Alloy System 49 Y. Kim, S. Das, M. Paliwal, and I. Jung

v

Experiments and Modeling of Fatigue of an Extruded Mg AZ61 Alloy 55 J. Jordon, J. Gibson, and M. Horstemeyer

Low-Cycle Fatigue Behavior of Die-Cast Mg Alloy AZ91 61 L. Rettberg, W. Anderson, andJ. Jones

Small Fatigue Crack Growth Observations in an Extruded Magnesium Alloy 67 J. Bernard, J. Jordon, and M. Horstemeyer

Applicability of Mg-Zn-(Y, Gd) Alloys for Engine Pistons 73 K. Okamoto, M. Sasaki, N. Takahashi, Q. Wang, Y. Gao, D. Yin, and C. Chen

Compressive Creep Behaviour of Extruded Mg Alloys at 150 °C 79 M. Fletcher, L. Bichler, D. Sediako, andR. Klassen

The Effect of Thermomechanical Processing on The Creep Behavior and Fracture Toughness of Thixomolded® Am60 Alloy 85

Z. Chen, A. Shyam, J. Howe, J. Huang, R. Decker, S. LeBeau, and G Boehlert

Casting and Solidification Simulation of Porosity and Hot Tears in a Squeeze Cast Magnesium Control Arm 93

C. Beckermann, K. Carlson, J. Jekl, andR. Berkmortel

Dendritic Microstructure in Directional Solidification of Magnesium Alloys 101 M. Amoorezaei, S. Gurevich, andN. Provatas

Microstructures and Casting Defects of Magnesium Alloy Made by a New Type of Semisolid Injection Process ..107 Y. Murakami, N. Omura, M. Li, T. Tamura, S. Tada, andK. Miwa

Macrostructure Evolution in Directionally Solidified Mg-RE Alloys 113 M. Salgado-Ordorica, W. Punessen, S. Yi, J. Bohlen, K. Kainer, andN. Hort

Microstructure and Mechanical Behavior of Cast Mg AZ31-B Alloy Produced by Magnetic Suspension Melting Process 119

N. Rimkus, M. Weaver, andN. El-Kaddah

Investigations on Hot Tearing of Mg-Zn-(Al) Alloys 125 L. Zhou, Y. Huang, P. Mao, K. Kainer, Z. Liu, andN. Hort

Proportional Strength-Ductility Relationship of Non-SF6 Diecast AZ91D Eco-Mg Alloys 131 S. Kim

Estimation of Heat Transfer Coefficient in Squeeze Casting of Magnesium Alloy AM60 by Experimental Polynomial Extrapolation Method 137

Z. Sun, X. Niu, and H. Hu

Wide Strip Casting Technology of Magnesium Alloys 143 W. Park, J. Kim, I. Kim, andD. Choo

Microstructural Analysis of Segregated Area in Twin Roll Cast Mg Alloy Sheet 147 J. Kim, W. Park, andD. Choo

Development of the Electromagnetic Continuous Casting Technology for Mg Alloys 151 J. Park, M. Kim, J. Kim, G. Lee, U. Yoon, and W. Kim

vi

Alloy Design/Development: Grain Refinement and Severe Plastic Deformation Effect of Zn/Gd Ratio on Phase Constitutions in Mg-Zn-Gd Alloys 157

S. Zhang, G Yuan, C. Lu, and W. Ding

Optimization of Magnesium-Aluminum-Tin Alloys for As-Cast Microstructure And Mechanical Properties 161 X. Kang, A. Luo, P. Fu, Z. Li, T. Zhu, L. Peng, and W. Ding

Thermodynamic Analysis of As-cast and Heat Treated Microstructures of Mg-Ce-Nd Alloys 167 M Easton, S. Zhu, M. Gibson, J. Nie, J. Groëbner, A. Kozlov, andR. Schmid-Fetzer

Compressive Strength and Hot Deformation Behavior of TX32 Magnesium Alloy with 0.4% Al and 0.4% Si Additions 169

K. Rao, Y. Prasad, K. Suresh, C. Dharmendra, N. Hort, and K. Kainer

An Analysis of the Grain Refinement of Magnesium By Zirconium 175 P. Saha, andS. Viswanathan

Study on the Grain Refinement Behavior of Mg-Zr Master Alloy and Zr Containing Compounds in Mg-10Gd-3Y Magnesium Alloy 181

G. Wu, M. Sun, J. Dai, and W. Ding

The Effect of Rare Earth Elements on the Texture and Formability of Shear Rolled Magnesium Sheet 187 D. Randman, B. Davis, M. Alderman, G Muralidharan, T. Muth, W. Peter, T. Watkins, andO. Cavin

Improvement of Strength and Ductility of Mg-Zn-Ca-Mn Alloy by Equal Channel Angular Pressing 195 L. Tong, M. Zheng, S. Xu, P. Song, K. Wu, and S. Kamado

Deformation Behavior of a Friction Stir Processed Mg Alloy 199 Q. Yang, S. Mironov, Y. Sato, andK. Okamoto

Effect of Heat Index on Microstructure and Mechanical Behavior of Friction Stir Processed AZ31 205 W. Yuan, andR. Mishra

Strengthening Mg-Al-Zn Alloy by Repetitive Oblique Shear Strain 211 T. Mukai, H. Somekawa, A. Singh, and T. Inoue

High-Temperature Alloys; High-Strength Alloys: Precipitation Creep and Elemental Partitioning Behavior of Mg-Al-Ca-Sn Alloys with the Addition of Sr 217

J. TerBush, O. Chen, J. Jones, and T. Pollock

Effect of Mn Addition on Creep Property in Mg-Al-2Ca Systems 223 T. Homma, S. Nakawaki, K. Oh-ishi, K. Hono, andS. Kamado

The Effect of Precipitate State on the Creep Performance of Mg-Sn Alloys 227 M. Gibson, X. Fang, C. Bett les, and G Hutchinson

Microstructure and Mechanical Properties of Mg-Zn-Y-M (M: Mixed RE) Alloys with LPSO Phase 229 J. Kim, and Y. Kawamura

Application of Neutron Diffraction in Characterization of Texture Evolution During High-Temperature Creep in Magnesium Alloys 233

D. Sediako, S. Shook, S. Vogel, and A. Sediako

vu

Improved Processing of Mg-Zn-Y Alloys Containing Quasicrystal Phase for Isotropie High Strength and Ductility 239

A. Singh, Y. Osawa, H Somekawa, and T. Mukai

Precipitation Hardenable Mg-Ca-Al Alloys 245 J. Jayaraj, C. Mendis, T. Ohkubo, K. Oh-ishi, and K. Hono

Microstructure, Phase Evolution and Precipitation Strengthening of Mg-3.lNd-0.45Zr-0.25Zn Alloy 249 G Atiya, M. Bamberger, and A. Katsman

Precipitation Process in Mg-Nd-Zn-Zr-Gd/Y Alloy 255 J. Li, G. Sha, P. Schumacher, and S. Ringer

Mechanical Properties and Microstructures of Twin-roll Cast Mg-2.4Zn-0.lAg-0.lCa-0.16Zr Alloy 261 C. Mendis, J. Bae, N. Kim, and K. Hono

The Solidification Microstructure and Precipitation Investigation of Magnesium-rich Alloys Containing Zn and Ce 267

C. Zhang, A. Luo, and Y. Chang

Deformation Mechanisms I Crystal Plasticity Analysis on Compressive Loading of Magnesium with Suppression of Twinning 273

T. Mayama, T. Ohashi, K. Higashida, and Y. Kawamura

Crystal Plasticity Modeling of Pure Magnesium Considering Volume Fraction of Deformation Twinning 279 Y. Tadano

Nucleation Mechanism for Shuffling Dominated Twinning in Magnesium 285 S. Kim, H. ElKadiri, and M. Horstemeyer

On the Impact of Second Phase Particles on Twinning in Magnesium Alloys 289 M. Barnett, N. Stanford, J. Geng, andJ. Robson

Influence of Crystallographic Orientation on Twin Nucleation in Single Crystal Magnesium 295 C. Barrett, M. Tschopp, H. El Kadiri, and B. Li

Twinning Multiplicity in an AM30 Magnesium Alloy Under Uniaxial Compression 301 Q. Ma, H. El Kadiri, A. Oppedal, J. Baird, and M. Horstemeyer

Inhomogeneous Deformation of AZ31 Magnesium Sheet in Uniaxial Tension 307 J. Kang, D. Wilkinson, andR. Mishra

Limitation of Current Hardening Models in Predicting Anisotropy by Twinning in HCP Metals: Application to a Rod-textured AM30 Magnesium Alloy 313

A. Oppedal, H. El Kadiri, C. Tome, J. Baird, S. Vogel, and M. Horstemeyer

Deformation Behavior of Mg from Micromechanics to Engineering Applications 321 E. Lilleodden, J. Mosler, M. Homayonifar, M. Nebebe, G. Kim, andN. Huber

Effect of Substituted Aluminum in Magnesium Tension Twin 325 K. Solanki, A. Moitra, and M. Bhatia

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Deformation Mechanisms II; Formabilitv and Forming Influence of Solute Cerium on the Deformation Behavior of an Mg-0.5wt.% Ce Alloy 333

L. Jiang, J. Jonas, andR. Mishra

Texture Weakening Effect of Y in Mg-Zn-Y System 339 S. Farzadfar, M. Sanjari, I. Jung, E. Es-Sadiqi, andS. Yue

In-Situ Scanning Electron Microscopy Comparison of Microstructure and Deformation Behavior between WE43-F and\VE43-T5 Magnesium Alloys 345

T. Sano, J. Yu, B. Davis, R. DeLorme, andK. Cho

A Molecular Dynamics Study of Fracture Behavior in Magnesium Single Crystal 349 T. Tang, S. Kim, M. Horstemeyer, and P. Wang

Microstructural Relationship in the Damage Evolution Process of an Az61 Magnesium Alloy 357 M. Lugo, J. Jordon, M. Horstemeyer, and M. Tschopp

Formability Enhancement in Hot Extruded Magnesium Alloys 363 R. Mishra, A. Gupta, R. Sikand, A. Sachdev, andL. Jin

Deformation and Evolution of Microstructure and Texture during High Speed Heavy Rolling of AZ31 Magnesium Alloy Sheet 369

T. Sakai, A. Hashimoto, G. Hamada, andH. Utsunomiya

Formability of Magnesium Sheet ZE10 and AZ31 with Respect to Initial Texture 373 L. Stutz, J. Bohlen, D. Letzig, andK. Kainer

Hot Workability of Alloy WE43 Examined using Hot Torsion Testing 379 F. Polesak, B. Davis, R. DeLorme, andS. Agnew

Enhancement of Superplastic Forming Limit of Magnesium Sheets by Counter-Pressurizing 385 W. Bang, H. Lee, H. Kim, and Y. Chang

Microstructural Evolution during Roller Hemming of AZ31 Magnesium Sheet 389 A. Levinson, R. Mishra, J. Carsley, R. Doherty, and S. Kalidindi

The Warm Forming Performance of Mg Sheet Materials 395 P. Krajewski, P. Friedman, andJ. Singh

New Applications (Biomédical and Other) Current Research Activities of Biomédical Mg Alloys in China 399

Y. Zheng

Design Considerations for Developing Biodegradable Magnesium Implants 401 H. Brar, B. Keselowsky, M. Sarntinoranont, andM. Manuel

Coating Systems for Magnesium-Based Biomaterials - State of the Art 403 M. Staiger, andJ. Waterman

Corrosion, Surface Modification and Biocompatibility of Mg and Mg Alloys 409 S. Virtanen, andB. Fabry

IX

Magnesium Alloys For Bioabsorbable Stents: A Feasibility Assessment 413 C. Deng, R. Radhakrishnan, S. Larsen, D. Boismier, J. Stinson, A. Hotchkiss, J. Weber, T. Scheuermann, andE. Petersen

Processing Aspects of Magnesium Alloy Stent Tube 419 R. Werkhoven, W. Sillekens, andK. vanLieshout

Ballistic Analysis of New Military Grade Magnesium Alloys for Armor Applications 425 T. Jones, andK. Kondoh

Mg17Al12 Intermetallic Prepared by Bulk Mechanical Alloying 431 K. Sakuragi, M. Sato, T. Honjo, and T. Kuji

Corrosion Behaviour of Mg Alloys in Various Basic Media: Application of Waste Encapsulation of Fuel Decanning from UNGG Nuclear Reactor 435

D. Lambertin, A. Blachere, F. Frizon, and F. Bart

Advanced Materials and Processing Characterization of Hot Extruded Mg/SiC Nanocomposites Fabricated by Casting 443

S. Nimityongskul, N. Alba-Baena, H. Choi, M. Jones, T. Wood, M. Sahoo, R. Lakes, S. Kou, andX. Li

Effects of Silicon Carbide Nanoparticles on Mechanical Properties and Microstructure of As-Cast Mg-12wt.% Al-0.2wt.% Mn Nanocomposites 447

H. Choi, H. Konishi, andX. Li

Thermally-Stabilized Nanocrystalline Mg-Alloys 453 S. Mathaudhu, K. Darling, andL. Kecskes

TiNi Reinforced Magnesium Composites by Powder Metallurgy 457 Z. Esen

Nanocrystalline Mg-Matrix Composites with Ultrahigh Damping Properties 463 B. Anasori, S. Amini, V. Presser, and M. Barsoum

Effect of Fiber Reinforcement on Corrosion Resistance of Mg AM60 Alloy-based Composites in NaCl Solutions 469

Q. Zhang, and H. Hu

The Production of Powder Metallurgy Hot Extruded Mg-Al-Mn-Ca Alloy with High Strength and Limited Anisotropy 475

A. Elsayed, J. Umeda, and K. Kondoh

Thermal Effects of Calcium and Yttrium Additions on the Sintering of Magnesium Powder 481 P. Burke, C. Petit, S. Yakoubi, and G. Kipouros

Microstructure and Mechanical Properties of Solid State Recycled Mg Alloy Chips 485 K. Matsuzaki, Y. Murakoshi, and T. Shimizu

Corrosion and Coatings Salt Spray Corrosion of Mechanical Junctions of Magnesium Castings 493

S. Grassini, P. Matteis, G. Scavino, M. Rossetto, andD. Firrao

x

Comparing the Corrosion Effects of Two Environments on As-Cast and Extruded Magnesium Alloys 501 H. Martin, C. Walton, J. Danzy, A. Hicks, M. Horstemeyer, and P. Wang

Influence of Lanthanum Concentration on the Corrosion Behaviour of Binary Mg-La Alloys 507 D. Hoche, R. Campos, C. Blawert, and K. Kainer

Cryogenic Burnishing of AZ31B Mg Alloy for Enhanced Corrosion Resistance 513 Z. Pu, G. Song, S. Yang, O. Dillon, D. Puleo, and I. Jawahir

Advanced Conversion Coatings for Magnesium Alloys 519 S. Nibhanupudi, and A. Manavbasi

Development of Zirconium-based Conversion Coatings for the Pretreatment of AZ91D Magnesium Alloy Prior to Electrocoating 523

J. Reck, Y. Wang, and H Kuo

Use of an AC/DC/AC Electrochemical Technique to Assess the Durability of Protection Systems for Magnesium Alloys 531

S. Song, R. McCune, W. Shen, and Y. Wang

Effects of Oxidation Time on Micro-arc Oxidized Coatings of Magnesium Alloy AZ91D in Aluminate Solution 537

W. Mu, Z. Li, J. Du, R. Luo, and Z. Xi

Composite Coatings Combining PEO layer and EPD Layer on Magnesium Alloy 543 Y. Jiang, K. Yang, and Y. Bao

Poster Session Growth Kinetics of Y-Al12Mg]7 and ß-Al3Mg2 Intermetallic Phases in Mg vs. Al Diffusion Coupes 549

S. Brennan, K. Bermudez, N. Kulkarni, and Y. Sohn

Development and Characterization of New AZ41 and AZ51 Magnesium Alloys 553 M. Alam, H. Samson, A. Hamouda, Q. Nguyen, and M. Gupta

Engineering a More Efficient Zirconium Grain Refiner For Magnesium 559 S. Viswanathan, P. Saha, D. Foley, andK. Hartwig

Microstructure and Mechanical Properties of Mg-1.7Y-1.2Zn Sheet Processed by Hot Rolling and Friction Stir Processing 565

V. Jain, J. Su, R. Mishra, R. Verma, A. Javaid, M. Aljarrah, andE. Essadiqi

The Microstructure and Mechanical Properties of Cast Mg-5Sn Based Alloys 571 M. Keyvani, R. Mahmudi, and G. Nayyeri

Effect of Cooling Rate and Chemical Modification on the Tensile Properties of Mg-5wt. % Si Alloy 577 F. Mirshahi, M. Meratian, M. Zahrani, andE. Zahrani

On Predicting the Channel Die Compression Behavior of HCP Magnesium AM30 using Crystal Plasticity FEM 583

Q. Ma, E. Marin, A. Antonyraj, Y. Hammi, H. El Kadiri, P. Wang, and M. Horstemeyer

Investigation of Microhardness and Microstructure of AZ31 Alloy after High-Pressure Torsion 589 J. Vrâtnâ, M. Janecek, J. Strâsky, H. Kim, andE. Yoon

Plastic Deformation of Magnesium Alloy Subjected to Compression-First Cyclic Loading 595 S. Lee, M. Gharghouri, andJ. Root

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Microstructure Evolution in AZ61L During TTMP and Subsequent Annealing Treatments 599 T. Berman, W. Donlon, R. Decker, J. Huang, T. Pollock, andJ. Jones

Modeling the Corrosive Effects of Various Magnesium Alloys Exposed to Two Saltwater Environments 605 H. Martin, C. Walton, J. Danzy, A. Hicks, M. Horstemeyer, and P. Wang

Corrosion Performance of Mg-Ti Alloys Synthesized by Magnetron Sputtering 611 Z Xu, G. Song, andD. Haddad

Structure and Mechanical Properties of Magnesium-Titanium Solid Solution Thin Film Alloys Prepared by Magnetron-sputter Deposition 617

D. Haddad, G Song, and Y. Cheng

Effect of Adding Si02-Al203 Sol into Anodizing Bath on Corrosion Resistance of Oxidation Film on Magnesium Alloy 623

H. Liu, L. Zhu, and W. Li

Monotonie and Fatigue Behavior of Mg Alloy in Friction Stir Spot Welds: An International Benchmark Test in the "Magnesium Front End Research and Development" Project 629

H. Badarinarayan, S. Behravesh, S. Bhole, D. Chen, J. Grantham, M. Horstemeyer, H. Jahed, J. Jordon, S. Lambert, H. Patel, X. Su, and Y. Yang

Appendix

Controlling the Biodegradation Rate of Magnesium-Based Implants through Surface Nanocrystallization Induced by Cryogenic Machining Implants through Surface Nanocrystallization Induced by Cryogenic Machining 637

Z. Pu, D. Puleo, O. Dillon, and I. Jawahir

Author Index 643

Subject Index 647

xn

PREFACE

The world of today faces a number of immense challenges relating to such diverse issues as sustainability (environmental concerns, long-term availability of energy and mineral resources), security and quality of life. Most interestingly, magnesium can - and likely will - increasingly contribute to the resolution of several of these issues. Weight saving by introducing magnesium alloy components in vehicles is a recognized means of enhancing fuel efficiency and thus of reducing energy consumption and greenhouse gas emissions. Different from several other metals, magnesium is virtually inexhaustibly available from natural resources. By using attributes of magnesium-based materials other than low density (such as impact resistance, bio-compatibility and chemical affinity), a variety of new applications relating to ballistic armor, biomédical implants and hydrogen storage rises at the horizon.

It is against this background that the Magnesium Committee of the Light Metals Division of TMS has organized and sponsored its 12th edition of the Magnesium Technology Symposium, held at the TMS Annual Meeting in San Diego, CA (USA) from February 28 to March 3, 2011. The symposium was organized in an opening session, a poster session and nine technical oral sessions, covering a broad range of topics. This included primary production and characterization, casting and solidification, alloy design, high-temperature and high-strength alloys, deformation mechanisms, formability and forming, new applications, advanced materials and processing, and corrosion and coatings.

The volume at hand represents the Proceedings of this Symposium. Like in previous years, contributions come from countries around the globe that are active in magnesium research and development and reflect the latest advancements in the field. To ensure TMS standards, all papers were peer reviewed by a pool of volunteers acting on behalf of the Magnesium Committee. In addition to these Proceedings, some Symposium contributions on biomédical applications will be published in full in an upcoming JOM Special Issue sponsored by the Magnesium Committee and entitled "Biomédical Applications of Magnesium" (issue 63/4, April 2011).

The bar chart on the next page visualizes the development of the TMS Magnesium Technology Symposium since its inception in the year 2000 in terms of size and international participation. In the initial years, the number of contributions was quite steady, but as of 2005 when parallel sessions were introduced this number rose steeply - although variations between the successive years exist. Contributing countries can roughly be divided into two categories, depending on if their market emphasis is on magnesium supply (e.g., China and Israel) or consumption (e.g., Germany, Japan and the USA). The largest share of the Proceedings publications comes from the listed eight countries while the remaining category "others" comprises more than 20 other countries from Europe and Asia (with the United Kingdom and Norway being the most prominent of these). Overall, the USA accounts for roughly a quarter of all abstracts and papers to date, followed by Canada (14%), China (11%) and Germany (10%). Notably, the chart also reflects the market changes that the magnesium sector has seen over the last decade, the most pronounced example of this being the large increase in Chinese contributions along with the country's development of primary and alloy production during the more recent years.

Xlll

Keystone data of the TMS Magnesium Technology Proceedings (country of origin of each contribution is based on the affiliation of the main author)

The organization of the Magnesium Technology Symposium and the realization of its Proceedings would not have been possible without the support of numerous engaged volunteers. Hence this is the place to acknowledge the contribution of all authors, reviewers and session chairs that have been instrumental in making this happen. Further, the continued support by TMS staff has definitely facilitated the job and is well-appreciated.

While Symposium Proceedings traditionally reflect the state-of-the-art and spirit of the age, may this volume become a valuable part of your reference library for the years to come and in retrospect mark a memorable period in advancing the field of magnesium technology.

Wim H. Sillekens Sean R. Agnew Neale R. Neelameggham Suveen N. Mathaudhu

XIV

ABOUT THE EDITOR

WIM SILLEKENS MAGNESIUM TECHNOLOGY 2011 EDITOR

Wim H. Sillekens (1963) is a Senior Scientist at the Netherlands Organization for Applied Scientific Research (TNO), where he is involved in national and European research projects. He obtained his Ph.D. from the University of Technology Eindhoven, Netherlands, on a subject relating to metal-forming technology. Since he has been engaged in light-metals research (aluminum and magnesium), amongst others on (hydro-mechanical) forming, (hydrostatic) extrusion, forging, recycling/refining, and more recently on biomédical applications. His professional career includes positions as post-doc researcher at his alma mater and as a research scientist / project leader at TNO. International working experience covers a placement as a research fellow at the Mechanical Engineering Laboratory (AIST-MITI) in Tsukuba, Japan, and - more recently - shorter stays as a visiting scientist at GKSS in Geesthacht, Germany, and at PNNL in Richland WA, USA. He has co-authored a variety of journal and conference papers (about 50 entries to date). Current research interests are in the physical and mechanical metallurgy of light metals in general and magnesium wrought alloys in particular.

XV

ABOUT THE ORGANIZERS

Sean R. Agnew is the Heinz and Doris Wilsdorf Distinguished Research Chair and Associate Professor in the Department of Materials Science and Engineering at the University of Virginia. He earned his Ph.D. in Materials Science and Engineering at Northwestern University in 1998. His dissertation focused on fatigue behavior and texture of ultrafine grain copper produced by severe plastic deformation. He first began working on magnesium as a Wigner post-doctoral fellow at the Oak Ridge National Laboratory in 1999, with research into the mechanical behavior of both cast and wrought alloys. Since moving to UVA in 2001, his magnesium research has focused on the development of constitutive models that account for dislocation- and twinning-based deformation mechanisms; modeling and control of texture development; measurement and modeling of the hot workability and sheet metal formability; and alloy design. His research group also conducts research on fatigue, creep, diffraction-based characterization, and non-destructive testing of a variety of metallic alloys.

Neale R. Neelameggham is the Technical Development Scientist for US Magnesium LLC. He has 38 years of expertise in magnesium production technology, having been with the plant from its startup company NL magnesium. Dr. Neelameggham's expertise includes all aspects of the magnesium process, from solar ponds through the cast house including solvent extraction, spray drying, molten salt chlorination, electrolytic cell and furnace designs, lithium ion battery chemicals and by-product chemical processing. In addition, he has an in-depth and detailed knowledge of alloy development as well as all competing technologies of magnesium production, both electrolytic and thermal processes worldwide. Dr. Neelameggham holds 13 patents and has several technical papers to his credit. As a member of TMS, AIChE, and a former member of American Ceramics Society he is well versed in energy engineering, bio-fuels and related processes. Dr. Neelameggham has served in the Magnesium Committee of LMD since its inception in 2000, chaired it in 2005, and has been a co-organizer of the Magnesium Symposium since 2004. In 2007 he was made a Permanent Co-organizer for the Magnesium Symposium. He has been a member of the Reactive Metals Committee, Recycling Committee and Programming Committee Representative of LMD. In 2008, LMD and EPD created the Energy Committee following the symposium on CO2 Reduction Metallurgy Symposium initiated by him. Dr. Neelameggham was selected as the inaugural Chair for the Energy Committee with a two-year term. He is also a member of LMD council. Dr. Neelameggham holds a doctorate in extractive metallurgy from the University of Utah.

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Suveen N. Mathaudhu is a Program Manager with the US Army Research Office (ARO), Materials Science Division. Dr. Mathaudhu also concurrently serves as an Adjunct Assistant Professor in the Department of Materials Science and Engineering at North Carolina State University. Dr. Mathaudhu received his B.S.E. from Walla Walla College and his Ph.D. in Mechanical Engineering from Texas A&M University. Upon graduating in 2006, he accepted a post-doctoral fellowship, and subsequently a civil servant position at the US Army Research Laboratory with the purpose of establishing deformation-processing laboratories for research on advanced metallic and composite materials. Since joining ARO in 2010, he manages programs which focus on the use of innovative approaches for processing high performance structural materials reliably and at lower costs. Dr. Mathaudhu's current research interests include: ultrafine-grained and nanostructured materials by severe plastic deformation, microstructural optimization and homogenization, consolidation of metastable particulate materials and processing-microstructure-property relationships of refractory metals and lightweight metals, integrated computational materials engineering, and thermally stable nanocrystalline materials. He has co-authored over 40 technical publications in these areas. He is also an active member of TMS where he is the primary organizer of the Ultrafine-Grained Material Symposium, and also serves on the Magnesium Technology Committee, and the Nanomaterials Committee.

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Magnesium Technology 2011 Opening Session

Session Chairs:

Wim H. Sillekens (TNO Science and Industry, Netherlands)

Suveen N. Mathaudhu (US Army Research Office, USA)

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Magnesium Technology 2011 Edited by: Wim H. Sillekens, Sean R. Agnew, Neale R. Neelameggham, andSuveen N. Malhaudhu

TMS (The Minerals, Metals & Materials Society), 2011

MAGNESIUM IN NORTH AMERICA: A CHANGING LANDSCAPE

Susan Slade US Magnesium LLC; 238 North 2200 West; Salt Lake City, UT 84116, USA

Keywords: magnesium market, North America

Abstract

The changing landscape of North American manufacturing in the context of global competition is impacting the market of all raw materials, including magnesium. Current automotive fuel economy legislation and pending legislation on the emissions of greenhouse gases are impacting magnesium's largest consuming industries, such as aluminum, automotive components, steel and transition metals. These industries are all considering innovative ways to efficiently incorporate the needed raw materials into their processes. The North American magnesium market differs from other regions based on maturity, supply streams, changing manufacturing capabilities and trade cases, combined with the transformation of North American manufacturing.

The impact of these factors on the supply/demand dynamics of the North American magnesium market in both the short and long-term will be reviewed. The influence of new applications, products, and legislative changes are considered in the equation.

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Magnesium Technology 2011 Edited by: Wim H. Sillekens, Sean R. Agnew, Neale R. Neelameggham, andSuveen N. Mathaudhu

TMS (The Minerals, Metals & Materials Society), 2011

GLOBAL MAGNESIUM RESEARCH: STATE-OF-THE-ART AND WHAT'S NEXT?

Karl Ulrich Kainer

Helmholtz Zentrum Geesthacht, Magnesium Innovation Center; Max-Planck-Straße 1, 21502 Geesthacht, Germany

Keywords: magnesium research and development, global situation, issues and challenges

Abstract

In recent years magnesium and its alloys have been successfully introduced into weight-saving applications in the transportation industries in order to reduce fuel consumption and greenhouse gas emissions as well as to increase the performance of modern cars. Besides advantages, e.g. superior specific strength and excellent processability, applications of magnesium alloys are limited due to their inferior properties at elevated temperatures, e.g. low creep resistance and reduced corrosion behavior, especially when in galvanic contact with other metallic materials.

Current developments are revealing possibilities to improve these properties by using modern alloys and processing routes. While the majority of industrial applications utilize cast products, the use of wrought magnesium alloys is still at an early stage. Within the framework of ongoing research and development, the corrosion behavior of both cast and wrought magnesium materials in standalone uses or in galvanic couples with other metallic materials is gaining increasing attention. New coating systems tailored to selected applications will have to be developed in order to increase the usage of magnesium alloys in the transportation industries in the future. This work also needs to be coordinated with new processes for joining magnesium alloys with similar and dissimilar metals and alloys, to achieve a broad spectrum of materials that fulfill the requirements given by the applications.

After years of intensive research in Europe, North America, Australia and Asia, an increase in these activities has taken place in recent years, in particular in China and Korea. The magnesium industry has to face new challenges with regard to market issues, the breakdown of the Western magnesium industry and finally the carbon footprint discussion of the life-cycle assessment of components for the transportation industry.

This presentation will first address these issues and challenges, then discuss new developments and finally show some examples of new applications. In the conclusions, gaps and challenges will be analyzed and recommendations for sustainable research and development will be given.

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Magnesium Technology 2011 Edited by: Wim H. Siilekens, Sean R. Agnew, Neale R. Neelameggham, andSuveen N. Mathaudhu

TMS (The Minerals, Metals & Materials Society), 2011

ENVIRONMENTAL CHALLENGES FOR THE MAGNESIUM INDUSTRY

Robert E. Brown Magnesium Assistance Group Inc; 226 Deer Trace; Prattville, Alabama 36067, USA

Keywords: magnesium production, environment, recycling

Abstract Electrolytic Magnesium Production

The subject of environmental concerns with magnesium production and magnesium processing first started showing up in technical analysis of problems about the time of Life Cycle Analysis articles. Magnesium is produced and processed in relatively small quantities throughout the world. Annual magnesium production has been around 500-700,000 metric tons per year. This compares to aluminum which is produced in annual amounts up to 35 million metric tons.

There have been some excellent review papers done, but a great amount of the work related to electrolytic magnesium production which was the predominant method of production. That situation has changed totally in the past 10 years and now 85% of the world's magnesium is produced by thermal processes and most of that is in China.

Comparison papers have been written on the environmental impacts of the two main magnesium production processes. As the measurement technology improves and as the total information references are better understood the environmental challenges can be more clearly identified. This paper reviews the situation and suggests some forward looking steps that might need to be taken.

Introduction

Most of the major environmental problem areas can be divided into the electrolytic magnesium and the thermal magnesium production methods. And these areas can again be subdivided into the preparation of the magnesium containing feed materials and the actual processing of this material to produce magnesium metal. All of these areas are impacted by secondary processes which impact the magnesium production such as the production of process power and necessary reduction materials such as 75% ferrosilicon for the Pidgeon thermal reduction process.

The first LCA papers were prompted by the environmental work that was done to get new construction permits for newer electrolytic magnesium plants planned for Canada and Australia in the late 1980's. The work was well done and focused on the GHG (Greenhouse Gas) effect. Some of the work was made part of investigations on the advantage of a lighter weight magnesium car in regard to emissions. For the first time, the advantage of SF6 as a cover was questioned because of its global warming potential. SF6 was found to have a global warming potential of 23,900 times that of Carbon Dioxide (C02) [1]. This problem was immediately addressed with a partnership between the U.S. Environmental Protection Agency (EPA) and the magnesium community. There were 16 members along with the International Magnesium Association that joined in this work [2]. At that time, the magnesium usage of SF6 amounted to about 7% of the total world usage. Initially this was estimated to be about 4 kg/metric ton of magnesium product. Later it was found to be closer to 2kg/mt [2].

Most electrolytic magnesium production plants have been closed. Some of the original LCA studies were done on the Norsk Hydro plants in Porsgrunn, Norway and Becancour, Québec, Canada [3]. The primary feed for Porsgrunn was sea water and dolomite. Feed for Becancour is magnesite. Total emissions from the two plants were included in the study by Albright and Haagensen. At the time, it was said, "Separate data for emissions from Porsgrunn and Becancour sites during the period 1994 to 1996 were charted. See Table I. For each of the emissions, the 1996 level at Porsgrunn is above the 1995 level at the Becancour plant. This difference arises from the fact that the Becancour plant was constructed with new, improved technology, whereas the older Porsgrunn facility is being continually improved from substantially higher emission levels a decade ago."

Table I. Emissions from Norsk Hydro Production Sites (1995-1996)

Site Pors-grunn Becan-cour

CHCto Water, kg

19961995 3.0 3.2

0.4 0.8

Dioxins to air, grams

1996 1995 1.3 3.5

0.42 0.51

Dioxins to water, grams

1996 1995 2.3 1.6

0.05 0.02

SO2 to air, tons

1996 1995 276 190

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Albright and Haagensen did not list the production capacities of the plants, although the published estimates for each of these plants were about 40,000 mtpy of capacity [4]. Chlorinated hydrocarbon (CHC) emissions were actually reduced by half at both plants. Dioxins decreased substantially. The authors pointed out, "that in 1997 the permitted values of total dioxin emissions for Porsgrunn are but two grams per year to atmosphere and one gram per year to the water" [5].

Further work on the electrolytic process was discussed in work done by scientists at the Commonwealth Scientific and Industrial Research Organization (CSIRO) in Australia [6]. Unfortunately they used the Australian Magnesium Corporation technology in their calculations. This process was run in a 1500 mtpy pilot operation, but the commercial plant was not constructed. Magnesite was used for me process feed.

The initial calculations were part of a study to assess the environmental impact of a magnesium engine block supply chain. This study also was broadened to include an engine block made from magnesium alloy ingots produced at Becancour and secondary ingots produced in the USA. The study concluded that "the use stage of a passenger car contributes significantly to the total GHG impact of magnesium components over their entire life cycle. A significant reduction in the GHG impact during the use stage, and hence over the entire life cycle, may be achieved from a

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significant mass reduction of a car by using magnesium components" [7].

A second study was run using a torque converter housing as the automobile part produced [8]. The results were very similar to the engine block study and showed a significant reduction only if there was the substitution of a cover gas which had a lower GWP than SF6 for the processing. A simple substitution of magnesium without a large reduction in GHG is not competitive environmentally with other metals such as demonstrated in the case of Chinese magnesium.

The development of the new electrolytic reduction plant designs, required environmental permitting and such items as chlorine emissions and dioxin generation were addressed in great detail. In the case of the work by Albright and Haagensen a LCI (Life Cycle Inventory) was developed for Norsk Hydro magnesium plants [3]. Clear tables were developed for both pure magnesium production and for magnesium alloy production. See Table II below.

In regard to the emissions and wastes at Norsk Hydro plants, it was reported that "The solid wastes from Hydro's plants consists mostly of inorganic salts and minerals from the raw materials. This waste is disposed of at authorized sites and does not cause any negative environmental impact. The treatment of gas and waste water on site, along with incineration of residues containing chlorinated hydrocarbons, form a portion of the (LCI) analysis as well."

Table II. Life Cycle Inventory for Magnesium Production [3]

Total Energy MJ/kg metal Global warming effect kg C O ^ k g Acidification kg/kg metal Winter Smog kg/kg metal Solid Waste kg/kg metal Dioxins to air ug/kg metal CHC to air mg/kg metal

Pure Mg 144 19 0.02 0.015 0.5 0.24 13.7

Mg Alloy AZ91 151 19 0.025 0.017 0.5 0.21 12.4

The subject of chlorinated hydrocarbons, dioxins and chlorine emissions to air is continually addressed in the design and operation of electrolytic magnesium reduction plants [11]. Newer and better scrubbing technology plus process modifications have made great steps in reducing the emissions. Although the construction of electrolytic plants continues to be slow, the research and development of the new equipment and methods should be encouraged on a global basis.

Thermal Reduction Processes

The silicothermic process has been investigated very carefully in several excellent papers [9, 10]. The basis for most of the work is the Pidgeon process as operated in most Chinese plants. Results of these studies indicate that direct comparison with electrolytically produced magnesium shows the GCI (Global Climate Impact) is much greater for the silicothermic process.

The papers qualify their calculations by noting that the Chinese production is continually being upgraded and the effects of these changes have greatly improved the GCI over the past ten years. One inherent advantage of the Chinese casting operations is that they use very small amounts of SF6 in the ingot casting operations.

This has mainly occurred because the majority of the first plants built in China were very rudimentary and used very simple melting and casting operations with sulfur powder directly dusted on the cast ingots to prevent burning during solidification. As the plants increased in size, most of the operations retained the sulfur dusting for convenience and simplicity.

The Chinese magnesium and ferrosilicon operations were impacted by the 2008 Olympic Games that were held in Beijing. A central approach was taken to drastically reduce emissions during this period. Many of the older and smaller Pidgeon process plants with inefficient collection equipment were forced to close to meet the strict guidelines issued. It is predicted that the central approach to control emissions and to encourage greater energy efficiency will continue. This has recently been seen by new rules that have been issued regarding the size and design of magnesium plants that would be given permits [12].

China, in its 12th Five-Year-Plan, is planning to control its annual national output of magnesium, aluminum, copper, nickel, lead, zinc, tin, antimony, titanium and mercury, with total production not exceeding 41 million mt/year until 2015, according to China Nonferrous Metals Industry Association [12].

The government plans to eliminate magnesium smelters with capacities belowl5,000 mt/year and requires existing plants to have a minimum smelting capacity of 15,000 mt/year, while new entrants must have a minimum capacity of 20,000 mt/year, Ministry of Industry and Information Technology, or MITT, officials said at a magnesium industry conference in Ningxia in October 2010 [12].

In Beijing, a source with China Magnesium Association (CMA) said, "The government's stricter regulations will be good to the domestic magnesium sector as these will help improve industry management, which is in line with the state's macro goal of energy saving and emissions reduction."

According to MITT, the proposed new regulations will require existing smelters to consume a maximum of 5.5-6.0 mt of coal for one ton of magnesium smelting, and for the new smelters, a maximum of 5 mt of coal. Chinese magnesium smelters, over the past few decades, have been consuming as much as 11-18 mt of coal for each ton of magnesium smelting, although some smelters in the last two years were able to cut the usage to around 5-6 mt coal, following the state's advocating a low-carbon economy, according to CMA [12].

The environmental impacts of the products must be compared throughout their entire life-cycle i.e. from "cradle-to-grave", and this is done by Life-cycle Assessment (LCA), also known as Life-cycle Analysis. LCA allows impacts to be assessed throughout all stages of production and use to final disposal.

A newer study has a focus on the global warming impact; a cradle-to-grave life cycle study is conducted using averaged data for magnesium production in China. Calculations show that the cradle-to-grave global warming impact of Chinese magnesium ingots is 42 kg C02 eq/kg Mg ingot, within an uncertain range of 37-41 kg C02 eq/kg Mg ingot. The value of impact for the magnesium produced in China IS rvj 60% higher than the global warming impact of aluminum, a competing material that is also produced in China in abundance [13].

The results of other recent studies show that the direct emission of fuel combustion in the process is the major contributor to the pollutants emission of magnesium production. Global warming potential and acidification potential make the main contribution to the accumulative environmental impact. The different fuel use strategies in the practice of magnesium production cause much different impacts on the environmental performance. The accumulative environmental impact of coal burned directly is the highest, and that of producer-gas comes to the next, while that of coke-oven gas is the lowest [13, 14].

Much of the fuel-based pollution will be addressed under the new rules and natural gas is being designed into many of the newer plants where it is available.

Discussion

We know that magnesium is the lightest structural metal and it is basically available in limitless quantities. The earth is literally covered with magnesium as one cubic mile of seawater contains 6,000,000 tons of magnesium and there are 330,000,000 cubic miles of seawater according to The Scientific American. There is magnesium in all of the major salt lakes in the world and it is found in deposits in various forms on all continents.

Unfortunately, it is not easy to recover economically due to some basic quirks of chemistry and the mechanical properties of the final metal produced have some serious limitations. The lightweight that makes magnesium as attractive as a material of construction is also a penalty in the modern method of calculation. Plants are rated in tons per day or tons per year. Extrusion presses are rated by tonnage. Rolling mills are rated by tonnage. Environmental emissions are rated by tonnage. One ton of magnesium is much larger than a ton of lead, hence it takes more material and more processing to produce the end product.

This phenomenon was discussed by Albright and Haagensen [3] where they say, "The energy consumption (at the primary plant site only) to produce magnesium and aluminum has been estimated as 35 and 30 kWh/kg. The comparative number for steel is about llkWhr/kg. However, when these data are considered on a unit volume basis, which is the common design concern (that is, components must be designed or packaged into a given space or volume), the life cycle advantage of magnesium is more clear. On this basis, the above numbers correspond to 63, 81, and 87 kWh/1 for magnesium, aluminum and steel, respectively. For recycled materials, the relative energy used is even more favorable for magnesium; with recycled magnesium energy consumption is only about lkWh/1."

Cherubini et al. [15] conclude that "World magnesium production contributes to the Global Warming Potential with an emission of about 25.5Mt of C02 eq. per year. This will be lowered as the substitutions and elimination of SF6 is taken into account with improved energy efficiency.

China has the higher emissions, but it is important to notice that while it supplies the Magnesium market with about 77% of total production, in terms of emissions it accounts for about 89.7% of the total: Mg industrial production in China is thus more polluting than in other countries, although, by an economic point of view, it is cheaper. This aspect is even more clearly shown by the Acidification Potential (where the contribution of Chinese Mg to

the total AP is equal to 93.1%), because of the relatively high sulfur content of the low-grade coal used in China [13].

These concerns are being addressed by several approaches in China and in the many major magnesium production research centers that they have recently established. The newest developments in China indicate that the major environmental challenges are being aggressively addressed by both private and governmental strategies.

The price of magnesium on a world wide basis is still quite high. Most of the small Chinese Pidgeon process plants that used coal for firing and large quantities of hand labor are slowly disappearing. Larger, more efficient plants, with advanced technology for the process and equipment are being built. All areas of the Chinese metals and magnesium community has become very aware of the global climate situation and are working very hard to become cleaner and more energy efficient.

The Chinese are approaching the problem of addressing GWI by improving the production plants and working hard in downstream processing to produce lightweight magnesium products for use in bicycles, motorcycles, cars, trains and airplanes.

The China Magnesium Association (CMA) review of 2009 [16] said, in part: "China's magnesium industry still faces huge challenges of adjusting structure and transforming development mode in 2010. The capability of independent innovation and core competitiveness need to be promoted. It's a brand new topic and task to revive the increasing of magnesium output and improve economic benefits, to expand the domestic demand and guarantee the growth, and to make more breakthroughs in domestic consumption." CMA tried to outline a development layout for China's magnesium industry and bring forward some ideas in the face of weakening global demand for Chinese magnesium.

Developing more new technologies of conserving energy and reducing emissions, developing low-carbon magnesium industry -$- Developing and using high-efficient and energy-saving

MELZ double-chamber shaft kiln, direct heat-storage U-kiln and annular shaft kiln;

■v* Developing and using reduction furnace clean production system with vertical retort in which briquette is loading from the top and slag is dripping out of the bottom;

-$■ Developing and using new electric Magnetherm technology; -y- Developing electrolytic method of magnesium smelting; -v- Recycling the waste heat of magnesium residues; ■$■ Recycling carbon dioxide; ■$■ Exploiting new smelting technologies using olivine,

serpentine and brucite. Expanding magnesium application and boosting domestic consumption, trying to build innovative strategic alliances ■$• Chery, partnered with North University of China and Shanxi

Yinguang Huasheng Magnesium Co. Ltd, built a magnesium innovative strategic alliance in the aim of promoting magnesium alloy wheels' application on automobiles;

*>■ CHANA Automobile built an innovative strategic alliance cooperated with Chongqing Boao Mg-Al Manufacturing Co. Ltd. And Chongqing University in the aim of promoting magnesium alloy's mass application on automobiles;

■Y- Promoting magnesium alloy's application on trains. China will continue industrial restructuring for the purpose of optimizing magnesium industry and upgrading competitiveness.

Targets will be to achieve low carbon economy, symbolized with low energy consumption, low pollution and low emission, they are now orienting and guiding the business of industrial restructuring. China efforts should be stepped up to adjust the structure of product, industry and industrial distribution in terms of the Planning for Adjusting and Reviving of the Non-ferrous Industry. ■$• Main smelters are gradually congregated in resource- and

energy-intensive areas while processing companies are located in consumer-intensive areas;

■$■ More products of high-quality, high value-added, high technology content and high competitiveness are manufactured;

■$• The development mode of energy-saving, low emission, clean, safe and recycling is widely adopted.

Boosting China magnesium's quality and profitability by transforming development mode -$- To set up magnesium industry model bases and strength

their guide role by enhancing their ability of independent innovation, extending and maturing industry chain as well as expanding industrial scale;

<* To eliminate the under-developed capacity through competition. It is urgent requirement of transforming development mode and enhancing economic growth quality and profitability. It's also requirement of dealing effectively with financial crisis. Similarly, it is requirement of promoting energy-saving & emission-reducing and tackling global climate changes.

The Chinese review concluded by saying "In the era following the financial crisis of 2008, we believe that the global magnesium industry will have a bright and promising future only if international coordination and cooperation are being increased, only if the idea of win-win is being truly carried out, only if common challenges are being tackled jointly. "

The US Government is also moving more into taking control of the emissions of several areas including magnesium. The reporting of greenhouse gas emissions by major sources of these pollutants is gaining momentum [17].

The U.S. Environmental Protection Agency (EPA) is finalizing requirements under its national mandatory greenhouse gas (GHG) reporting program for underground coal mines, industrial wastewater treatment systems, industrial waste landfills and magnesium production facilities. The data from these sectors will provide a better understanding of GHG emissions and will help EPA and businesses develop effective policies and programs to reduce them.

It is encouraging that the total Global Warming Potential of the magnesium operations is being addressed. It has been reported that carmakers in the EU are cutting their fleets' carbon dioxide emissions faster than expected and will reach the European Union targets ahead of time [18].

Europe has instituted the REACH program which is also covering magnesium. The program is named for the description of Registration, Evaluation, Authorization and restriction of Chemicals. A group of companies with similar interests and handling the same class of materials can form a consortium. This has been done by many of the companies directly importing, using, or producing magnesium metal in Europe. A Substance

Information Exchange Forum (SIEF) has been established as a joint registration forum.

Over three months have passed since the first survey carried out by Magnesium REACH Consortium (MAREC) for its members' registration intention. The questionnaire covers the check of substance sameness, indication of envisaged registration deadline, registration intention, nomination of Lead Registrant (LR) and SIEF Formation Facilitator (SFF) and so on. Magnesium Elektron UK won the LR nomination, replacing previous ECKA Granulate Essen GmbH.

Magnesium (EC No.231-104-6) SIEF is a large SIEF with up to 2,441 members. However, it is unexpected that so far only 152 companies have given feedbacks. Furthermore, the number of SIEF members has sharply decreased to 104 now, which greatly increases individual costs. For this reason, MAREC has planned to launch another survey, which is the final survey for registration intentions of SIEF members [19].

In the meantime, it is reported that the use of SF6 gas has been eliminated in magnesium processing in Europe [20].

Conclusions

Magnesium as an industry has recognized the major problems with its position in Global Warming Potential. Many various companies, researchers, universities have responded rapidly and effectively to identify and address the problems. The largest problem areas have all had actions taken to quantify and address the problems.

China is the world leader in magnesium production and is making great efforts to mobilize an effective force to improve their environment. New magnesium production methods are being investigated and tested for favourable impact on the GWP. They have also started a REACH program and are cooperating with several European groups to get help in establishing their program. Magnesium was not specifically mentioned.

Europe continues to serve as a leader in its aggressive approach to overall analysis and addressing of the problems, including the use of Life Cycle Analysis (LCA) on the newer car designs.

The US EPA actively and positively stepped into the SF6 cover gas problem as have several producers of more environmentally friendly materials. The Australian research community is also working on cover gas development.

References

1. H. Gjestland, H. Westengen, S. Phahte, "Use of SF6 in the Magnesium Industry: An Environmental Challenge", Proceedings of the Third International Magnesium Conference, The Institute of Materials, London, 1997 pp 33-41. 2. S.C. Bartos, "Building a Bridge for Climate Protection: U. S. EPA and the Magnesium Industry", Proceedings of the 59th

Annual World Magnesium Conference (IMA), Montreal, Canada May 2002 pp 22-24. 3. D. Albright, J. Haagensen, "Life Cycle Inventory of Magnesium", Proceedings of the 54th Annual World Magnesium Conference (IMA), Toronto, Canada, June 1997 pp 32-37.

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