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Dr. Subodh K. Das. President & CEO Secat, Inc. Designing Aluminum Alloys for a Recycling Friendly World Presented To: Aluminum Association Sheet and Plate Division Spring Meeting Montreal, Canada April 24 th , 2006. Outline of Presentation. Recycling advantages and incentives
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Dr. Subodh K. Das President & CEO Secat, Inc. Designing Aluminum Alloys for a Recycling Friendly World Presented To:Aluminum Association Sheet and Plate Division Spring Meeting Montreal, Canada April 24th, 2006
Outline of Presentation • Recycling advantages and incentives • Recycled aluminum is the “new Urban Mine” • “Secondary“ is the new “Primary” • Opportunities to maximize recycling • Aluminum alloy design for recycling • Rationales • Opportunities • Recommendations • Looking to the future
Number of Primary Smelting Plants in the U.S. 2003: Fourteen (14) Smelters Operating SMELTERS OPERATING - 2003 • 8 Alcoa • 2 Century • 1 Alcan • 1 Norandal • 1 Ormet • 1 Columbia Falls ? SOURCE: LIGHT METAL AGE
U.S. Trends of Re-Melting vs. Smelting(000 Metric Tons) SOURCE: SECAT, INC.
Why Recycling? 1% change in recycling rate has an economic impact of approximately $12 million Trashed cans contribute about $600 million to the nation’s trade deficit each year National Aluminum Beverage Can Recycling Rate Trends.
Impact of Recycled Automotive Aluminum • Two largest areas are cans and autos • Can recovery reached ~67% in early 1990’s – now at ~50%; cultural, societal and technical issues • Auto metal recovery >90%; aided by regulations, shredders and lack of individual choice. • Recovery of Al from autos has exceeded all other scrap sources since 2005 • We have to learn to make as much new aluminum products as technically possible from recycled automotive aluminum in the US
Advantages of Aluminum Recycling • Recycling aluminum provides metal for 5% of energy invested in new primary aluminum and only 5% of CO2 produced • Economic savings to municipalities supports creation of new or enlarged recycling facilities • Domestic recycling reduces trade deficit and minimizes dependence on overseas metal sources • The price of alloying elements such as Cu, Mn, Mg, etc are rising at equal or higher rate than Al
Characteristics of the “Recycling Friendly World” • Ecology – Recycling and Consumption • Advanced Processing and Technology • Recycling Friendly Alloy Systems • High Value, Recycling Friendly Products • Good Public Awareness of Recycling
Challenges in Achieving the “Recycling Friendly World” • Improve efficiency of metal recovery • Increase effectiveness of shredding and sorting technology • Identify useful byproducts available through use of secondary scrap • Broaden range of alloys readily produced from recycled metal • Retain domestic aluminum scrap in US and lower exports to China and India
Recycling Successes to Recognize • Automotive Aluminum recovery and part pre-sorting • Laser induced breakdown spectroscopy (LIBS) for finer sorting after shredding • Alternative products such as “de-ox,” Fe-bearing aluminum for de-oxidizing steel
New Focus for Discussion – Optimizing Alloy Design for Recycling • Focuses on “properties” rather than “chemistry” • Requires careful consideration of challenges from higher impurity contents of recycled metal • Requires testing and qualification of new compositions for important applications • Revisits applicability and commercialization of the unialloy concept for packaging
Difficulties Utilizing Recycled Al Scrap Directly • Higher impurity levels • Fe buildup from equipment • Si levels from cast components • “Others” levels exceed AA limits • Special handling called for • Segregate wrought and cast alloys when practical • Target alloys for reusing recycled metal • To optimize use of recycled metal, new alloy options would be desirable
Design New Wrought Aluminum Alloys For Use of Recycled Metal • Useful preliminary rationale • Select compositions from each series representative of their strong points • Adjust limits on impurities to higher levels, potentially acceptable for many applications • Recognize implications of increased levels of impurities, and need to reset new limits based upon “performance” and not “chemistry”
More In-Depth Evaluation of Recycling Friendly Alloys Needed • Gain more specific information on the volume and compositions of aluminum alloy recycled from specific markets • Fine-tune candidate compositions of recycle-friendly alloys based upon findings • Critically evaluate wrought products made from proposed recycle-friendly alloys
Critical Evaluation of Recycling Friendly Alloys • Determine, among others: • Toughness • Formability • Corrosion resistance • Relate results to design requirements of intended applications, e.g., • Building & highway structures • Industrial piping & tanks • Consumer durables • Refine “compositions” as needed to obtain required “performance”
Conclusions • Advantages of recycling aluminum justify maximization of potential • Some successes to report in shredding, sorting, and alternative products • Inadequate attention given to optimizing alloy design for a recycle-friendly environment • Proposals put forth as to how such alloy design optimization might be approached • Evaluation testing to match performance requirements proposed
The Next Steps? • Establish recycling alloy optimization leadership team • Generate financial support • Phase 1 – Analyze volumetric recycling content by market • Phase 2 – Optimize new alloy compositions for use of recycled metal • Phase 3 – Evaluate properties and “performance” of new alloys, and adjust “chemistry” accordingly • Results will be published in Light Metals 2006 and presented at the annual TMS meeting in San Antonio in 2006 • Future research will be published in Light Metal Age (June 2006), International Aluminum Alloys Conference (July 2006) and Journal of Metals (August 2006)