Cast Materials Task Force Update/Deliverables Status NADCA R&D Committee Meeting Oak Ridge National Laboratory Oak Ridge, TN June 14, 2007

#137 Innovative Semi-Solid Metal (SSM) Processing Q. Y. Pan, P. Hogan, B. Dewhirst D. Apelian, M.M. Makhlouf Project Period: 06/1/04 through 6/30/07

Major Tasks  Task 1: Optimize the Continuous Rheoconversion Process (CRP) for commercial applications  Task 2: SSM alloy development  Task 3: Optimize heat treatment processes for SSM castings

Task 1 Achievements to Date  CRP can retrofit most die casting facilities (both vertical & horizontal machines)  CRP has been successfully scaled up for commercial applications; successful Beta trials conducted with numerous industrial partners (Buhler, THT Presses, Hayes-Lemmerz, Rheinfelden etc.)  Sound SSM castings were produced using a variety of commercial alloys (A356, 319, A206, Silafont-36 etc)  Some data for CRP operational window generated  More data for the operational window will be generated through additional industrial trials with ACRC Consortium members

CRP Processed Castings: Tensile Data  SSM vs. Squeeze Similar UTS & YS SSM: Slightly higher EL  SSM: T5 vs. T6 Excellent data under T6 A slight ductility loss under T5 (!!!)  Sr: no significant effect Observations:

 Established Criteria for SSM alloy optimization/design  Optimized 380/383/EN-AC46000, 206, 319, 6061 and 7075 alloys for SSM Applications  Optimal composition window established and recommended  Conducted Beta trials to validate simulation results  Newly developed Al-Zn-Mg alloys show potential for SSM applications Task 2 Achievements to Date

Task 3 Achievements to Date  Established optimal T5 HT schedule for SSM castings  Established optimal T6 HT schedule for SSM castings  Fluidized Bed heat treatment results are promising, with high strengths and QI

What’s Next?  Additional CRP Beta trials will be scheduled in July/August, 2007 at SAG  More T5/T6 samples will be produced and examined

Project Status/Update #139 Thin Wall Zinc  New Alloy developed with 40% higher fluidity than Alloy 7  Project meeting at NADCA Congress  2 trials planned for 2007 – conventional and 4-slide machines  Additional trial sites sought

Project Status/Update #144 Zinc Alloy Properties for Market Development Support  ILZRO, DOE ARC  Excel database sent to sponsors  Small amount of fatigue work remains to be done (3,5,8)  Creep work underway (2 and 5)

#144 Zinc Alloy Properties for Market Development Support  Database contents Tensile and compressive data between -40 and 135  C Flexural modulus curves Compressive test curves Coefficient of thermal expansion data, both showing changes in length with temperature and the slope of this data which is the coefficient. Fatigue data, including S-N and fatigue limit curves. Also data in which skin was removed vs. skin kept on the castings. Impact testing, both Charpy and Izod tests, including impact testing shows the impact energy vs. time. Impact testing at five temperatures between -40  and room temperature High strain rate testing, similar to the impact testing, in which stress/strain pairs are reported.

Project Status/Update #146 Die Casting Mechanical Property Improvements Through Process Enhancements  GM, WPI  Yet to start

Project Status/Update #152 High Production Rate Process for Metal Matrix Composite Components  CO School of Mines  Objective: Rapid production of composites using auto-ignition combustion synthesis:  Metal matrix, ceramic matrix & intermetallic matrix composites via squeeze DC & SSM  Predict 20-60% ceramics in PDC, 90% in squeeze DC & SSM

Progress  Produced 3 inch diameter x 4 inch cylinder with 47% TiC in an aluminum matrix  Acted like an SSM billet  Microstructural analyses performed  Mechanical testing to follow  Machining is very difficult

TiC Grain Size and Morphology 2) Grain size grows as TiC content increases due to increase in reaction temperatures. 1) Grain Size remains under 5 micron for small samples, ( grams) and 10 – 15 microns for 2 kilo sample lower photo

Project Status/Update # 153 AMC CIR program: High Performance Die Casting Alloys, WPI  Subtask: Target applications/alloy to be optimized; discussions with industry colleagues/partners. (Scheduled time; 3/1/06 - 8/31/06) Partnership established with Contech (formerly SPX); mechanical property improvement requirements under discussion.

# 153 AMC CIR program: High Performance Die Casting Alloys, WPI  Subtask: Use i-Select to optimize alloy(s) for the specified application. (Scheduled time; 6/1/06 - 9/30/06) Analyzed most possible requirements for Al die casting alloys using iSelect and have proposed composition ranges of target alloys. Focus on improving alloy properties, specifically strength, ductility, thermal conductivity, and surface finish etc., as well as improve alloy castability and corrosion resistance, and reduce costs

 Subtask: Cast samples of the select grade (premium grade) alloy – laboratory trials (Scheduled time; 10/2/06 - 3/29/07) 38 alloys cast and were examined in great detail by metallography and microstructural analysis; the following observations are made:  Mg at 2 to 4% significantly refines the Al-Si eutectic.  When Si content is between 10 to 15% all the other constituents within the eutectic structure are refined.  At 3%Mg, inclusions found when Si > 12%. Size and amount of the inclusions increased with increasing Si  Addition of Mn significantly changed the morphology of Fe-rich phases.  At lower Cu level the Cu-rich phase was in the form of clusters of small particles in the intergranular areas. With increasing Cu the particles became bigger and the string–like clusters became wider and agglomerated  Mechanical testing of selected alloys in progress

Project Review Dates #137 Innovative SSM Processing: During ACRC Meetings, 5/25 and 12/7/05, NADCA R&D 10/19/06, 10/17/07 #139 Thinwall Zinc: 10/19/06, 10/17/07 # 144 Zinc Alloys for Market Development Support: 2/23/06, 2/21/07

Project Review Dates (cont’d.) #146 Die Casting Mechanical Property Improvements Through Process Enhancements, 6/13/07 #152 High Production Rate Process for Metal Matrix Composite Components, 6/13/07 #153 High Performance Die Casting Alloys: 10/19/06, 10/17/07

Proposals for Balloting  #155 Plating and Finishing of Zinc Die Castings-Survey of Next Generation Finishes  #156 SSM Processing Databases for Designers and Metalcasters

Open Items  Status of Project Summaries for Completed Projects  Needed Research – Cast Materials Area

Ideas from February 21Task Force Meeting  Determination of compliance of all alloys in NADCA Product Standards with RoHS  Development of friction stir welding as replacement for traditional fastening techniques  Thin section die casting for Al, Mg alloys