STOCHASTIC MULTISCALE MODELING OF POLYCRYSTALLINE MATERIALS ADissertation PresentedtotheFacultyoftheGraduateSchool ofCornellUniversity inPartialFulfillmentoftheRequirementsfortheDegreeof DoctorofPhilosophy by BinWen January2013 Report Documentation Page Form Approved OMB No. 0704-0188 Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to a penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. 1. REPORT DATE 3. DATES COVERED JAN 2013 2. REPORT TYPE 00-00-2013 to 00-00-2013 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Stochastic Multiscale Modeling of Polycrystalline Materials 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION Cornell University,Sibley School of Mechanical and Aerospace REPORT NUMBER Engineering,169 Frank H. T. Rhodes Hall,Ithaca,NY,14853-3801 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S) 11. SPONSOR/MONITOR’S REPORT NUMBER(S) 12. DISTRIBUTION/AVAILABILITY STATEMENT Approved for public release; distribution unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF 18. NUMBER 19a. NAME OF ABSTRACT OF PAGES RESPONSIBLE PERSON a. REPORT b. ABSTRACT c. THIS PAGE Same as 225 unclassified unclassified unclassified Report (SAR) Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 ⃝c 2013BinWen ALLRIGHTSRESERVED STOCHASTICMULTISCALEMODELINGOFPOLYCRYSTALLINE MATERIALS BinWen,Ph.D. CornellUniversity2013 Mechanical properties of engineering materials are sensitive to the underly- ing random microstructure. Quantification of mechanical property variabil- ity induced by microstructure variation is essential for the prediction of ex- treme properties and microstructure-sensitive design of materials. Recent ad- vances in high throughput characterization of polycrystalline microstructures have resulted in huge data sets of microstructural descriptors and image snap- shots. Toutilizetheselargescaleexperimentaldataforcomputingtheresulting variability of macroscopic properties, appropriate mathematical representation of microstructures is needed. By exploring the space containing all admissi- ble microstructures that are statistically similar to the available data, one can estimate the distribution/envelope of possible properties by employing effi- cient stochastic simulation methodologies along with robust physics-based de- terministic simulators. The focus of this thesis is on the construction of low- dimensional representations of random microstructures and the development of efficient physics-based simulators for polycrystalline materials. By adopt- ing appropriate stochastic methods, such as Monte Carlo and Adaptive Sparse GridCollocationmethods,thevariabilityofmicrostructure-sensitiveproperties ofpolycrystallinematerialsisinvestigated. Theprimaryoutcomesofthisthesisinclude: • Developmentofdata-drivenreduced-orderrepresentationsofmicrostruc- turevariationstoconstructtheadmissiblespaceofrandompolycrystalline microstructures. • Development of accurate and efficient physics-based simulators for the estimationofmaterialpropertiesbasedonmesoscalemicrostructures. • Investigating property variability of polycrystalline materials using effi- cient stochastic simulation methods in combination with the above two developments. Theuncertaintyquantificationframeworkdevelopedinthisworkintegrates informationscienceandmaterialsscience,andprovidesanewoutlooktomulti- scale materials modeling accounting for microstructure and process uncertain- ties. Predictive materials modeling will accelerate the development of new ma- terialsandprocessesforcriticalapplicationsinindustry. BIOGRAPHICALSKETCH The author was born in the city of Shenyang, Liaoning Province, China, in November, 1983. After completing his high school education from Shenyang No. 120 Middle School, the author was admitted into the department of Aero- nautical Science and Engineering at Beijing University of Aeronautics and As- tronautics (BUAA) in 2002, from where he received his Bachelor’s degree in June, 2006, and the Master’s degree in June, 2008. In August 2008, the author enteredthedoctoralprogramattheSibleySchoolofMechanicalandAerospace Engineering, Cornell University, and was awarded another Master’s degree in January2011. iii ThisthesisisdedicatedtomyparentsGuipuWenandXiaojieAnfortheir constantsupportandencouragementtowardsacademicpursuitsduringmy schoolyears. iv ACKNOWLEDGEMENTS I would like to express my most sincere gratitude to my advisor, Professor Nicholas Zabaras, for his constant support, motivation and guidance over the lastfouryears. Hisinvaluablehelpandcarecovernotonlytheacademicwork, but also the life beyond lab. I would also like to thank Professors Christopher Earls and Derek Warner for serving on my special committee and for their en- couragementandsuggestionsduringthecourseofthiswork. Theirkindlyhelps areprecioustome. This research was supported by the Computational Mathematics program of AFOSR (grant F49620-00-1-0373), the Materials Design and Surface Engi- neering program of the NSF (award CMMI-0757824), the Mechanical Behav- ior of Materials program Army Research Office (proposal to Cornell University No. W911NF0710519),theComputationalMathematicsprogramofNSF(award DMS- 0809062) and an OSD/AFOSR MURI09 award to Cornell University on uncertainty quantification. This research used resources of the National En- ergy Research Scientific Computing Center, supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. Additional computing resources were provided by the NSF through TeraGrid resources provided by NCSA under grant number TG-DMS090007. I would like to thank the Sibley School of Mechanical and Aerospace Engineering for having supported me through a teaching assistantship for part of my study at Cornell. The computing codes were developed based on open source scientific computation libraries including PETSc, GSL, and FFTW. The academic license that allowed for these developments is appreciated. Finally, I would like to thank fellow MPDC members and other friends for their support during my daysatCornell. v TABLEOFCONTENTS BiographicalSketch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii Dedication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v TableofContents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi ListofTables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii ListofFigures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix 1 INTRODUCTION 1 2 UNCERTAINTY QUANTIFICATION AT A SINGLE MATERIAL POINT 11 2.1 Investigating mechanical response variability of single-phase polycrystallinemicrostructures . . . . . . . . . . . . . . . . . . . . 12 2.1.1 Modelreductiontheory . . . . . . . . . . . . . . . . . . . . 12 2.1.2 Microstructurerepresentationandreconstructionmethod- ology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2.1.3 Texturemodeling . . . . . . . . . . . . . . . . . . . . . . . . 24 2.1.4 Sparsegridcollocation . . . . . . . . . . . . . . . . . . . . . 30 2.1.5 Deterministicsolver . . . . . . . . . . . . . . . . . . . . . . 32 2.1.6 Numericalexamples . . . . . . . . . . . . . . . . . . . . . . 34 2.1.7 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 2.2 Investigating variability of fatigue indicator parameters of two- phasenickel-basedsuperalloymicrostructures . . . . . . . . . . . 50 2.2.1 Constructionofmicrostructurestochasticinputmodel . . 50 2.2.2 Polynomial chaos expansion of stochastic reduced-order model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 2.2.3 Thepre-imageprobleminKPCA . . . . . . . . . . . . . . . 63 2.2.4 Two-phasecrystalplasticityconstitutivemodel . . . . . . 66 2.2.5 Numericalexamples . . . . . . . . . . . . . . . . . . . . . . 72 2.2.6 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 3 UNCERTAINTY QUANTIFICATION OF MULTISCALE DEFORMA- TIONPROCESS 104 3.1 Microstructurerepresentation . . . . . . . . . . . . . . . . . . . . . 105 3.2 Bi-orthogonalKarhunen-Loe`vedecomposition . . . . . . . . . . . 107 3.3 Themultiscaledeterministicsolverandinputdataset . . . . . . . 113 3.3.1 Themultiscaledeterministicsolver . . . . . . . . . . . . . . 114 3.3.2 Initialsamplegeneration . . . . . . . . . . . . . . . . . . . 116 3.4 Numericalexamples . . . . . . . . . . . . . . . . . . . . . . . . . . 120 3.4.1 Constructionandvalidationofthereduced-ordermodel . 121 3.4.2 Stochasticmultiscaleforgingsimulation . . . . . . . . . . . 127 3.5 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131 vi 4 AN EFFICIENT IMAGE-BASED METHOD FOR MODELING THE ELASTO-VISCOPLASTIC BEHAVIOR OF REALISTIC POLYCRYS- TALLINEMICROSTRUCTURES 136 4.1 Crystalelasto-viscoplasticfastFouriertransformsimulator . . . . 137 4.1.1 Solutionofcrystalelasticboundaryvalueproblems . . . . 138 4.1.2 Solutionofcrystalvisco-plasticboundaryvalueproblems 142 4.1.3 Solution of crystal elasto-viscoplastic boundary value problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 4.1.4 CEPFFTalgorithm . . . . . . . . . . . . . . . . . . . . . . . 146 4.1.5 Anintegratedformulation . . . . . . . . . . . . . . . . . . . 148 4.2 Microstructuremodel . . . . . . . . . . . . . . . . . . . . . . . . . . 150 4.2.1 Discretization . . . . . . . . . . . . . . . . . . . . . . . . . . 151 4.2.2 Gridandtextureupdate . . . . . . . . . . . . . . . . . . . . 153 4.3 Numericalexamples . . . . . . . . . . . . . . . . . . . . . . . . . . 157 4.3.1 Basic formulation versus the augmented Lagrangian for- mulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158 4.3.2 Crystal elasto-viscoplastic FFT simulations for polycrys- tallinemicrostructures . . . . . . . . . . . . . . . . . . . . . 163 4.3.3 InvestigationoffatigueindicatorparametersofIN100 . . 173 4.3.4 Computationalefficiency . . . . . . . . . . . . . . . . . . . 179 4.4 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181 5 CONCLUSIONANDSUGGESTIONSFORFUTURERESEARCH 184 5.1 Multiscalemodelingofsuperalloysystems . . . . . . . . . . . . . 185 5.2 Uncertainty quantification with realistic polycrystalline mi- crostructures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186 5.3 Advanced methodologies for uncertainty analysis, property pre- dictionandmaterialdesign . . . . . . . . . . . . . . . . . . . . . . 188 Bibliography 190 vii