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Seminar Notice for Yash Pachaury's Preliminary Exam. Tuesday, Nov. 19, at 8:00 a.m., in ARMS 1021. "A Survey on Microstructure Analysis and Synthesis using Statistical Techniques
by Son, Rosemary E 18 Nov '19

18 Nov '19

Please consider attending the following: MATERIALS ENGINEERING SEMINAR "A Survey on Microstructure Analysis and Synthesis using Statistical Techniques" By Yash Pachaury Purdue MSE Preliminary Exam Advisor: Professor Anter El-Azab ABSTRACT Microstructure analysis and synthesis forms an essential part of establishing structure-property relationships of materials. Correlations between the different microstructural features, such as grain boundaries, inclusions and other defects, and the physical behavior of materials can reveal insights into the underlying mechanisms responsible for their observed behavior. For developing high fidelity computational tools, it becomes essential to extract different microstructural characteristics for studying the behavior of materials at different length and time scales. These microstructure characteristics can be utilized to reconstruct virtual microstructures to be used as an input to develop accurate microstructure dependent numerical models. This paper provides a review of different statistical techniques of microstructure analysis and synthesis to determine effective properties of multiphase materials and resolve microstructure dependent fields by explicitly introducing these features from experimental measurements into predictive models. This review provides an understanding of the microstructure correlation functions and the different paradigms such as phase recovery, simulated annealing and Markov random field-based approaches, which use these microstructural descriptors to reconstruct virtual microstructures to model the physical behavior of materials, including their effective structural response. Some areas of future research have been determined based on a critical assessment of different techniques. Date: Tuesday, November 19, 2019 Time: 8:00 A.M. Place: ARMS 1021

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Seminar Notice for Jorge Ramirez Velasco's Ph.D. Final Exam. Wednesday, Nov. 20, at 9:00 a.m., in ARMS 3115
by Son, Rosemary E 18 Nov '19

18 Nov '19

Please consider attending the following: MATERIALS ENGINEERING SEMINAR "The Effect of Biofuel Impurities on the Hot Corrosion of Yttria Stabilized Zirconia Thermal Barrier Coatings" By Jorge H. Ramirez Velasco Purdue MSE Ph.D. Final Exam Advisor: Professor Rodney W. Trice ABSTRACT Aircraft propulsion and industrial power generation have highlighted the critical role of gas turbines in modern society. Currently, components for these applications must withstand temperatures of at least 1400°C when operating within the combustor and the high-pressure sections of a gas turbine engine. With superalloys operating at its maximum capacity, ceramic multilayered materials systems known as thermal barrier coatings (TBCs) provide thermal and environmental protection to the engine's components. However, the introduction of biofuels into gas turbines applications has come with new challenges. The contaminants found in military and commercial biofuels are known to include oxides of alkali and alkaline earth metals and silicon oxides. While calcium-magnesium-aluminum silicates (CMAS) are typically ingested as particulate in volcanic ash and desert sand theaters, the impurity list in biofuels includes the necessary elements to form CMAS without exposure to any specific environment. CMAS is particularly destructive for operating temperatures above its melting temperature (~1250°C), mainly reducing yttria-stabilized zirconia (YSZ) TBCs lifetimes. Thus, identification of the corrosive compounds produced by the interaction of biofuel contaminants/TBCs and a specific understanding of its adverse effect is mandatory to avoid the failure of gas turbines. In this work, solutions containing the impurities of interest are prepared and sprayed onto TBCs simulating the deposit of the impurities during combustion. Subsequently, the TBCs are subject to thermal gradient testing up to 1400°C, and their microstructures evaluated. Date: Wednesday, November 20, 2019 Time: 9:00 A.M. Place: ARMS 3115

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Seminar Notice for R. G. Sreekar Annadanam's Preliminary Exam. Seminar Thursday, Nov. 21, 8:00 a.m., in ARMS 1103. "Void Formation and Evolution in Irradiated Metals Studied by Phase-Field Approach"
by Son, Rosemary E 18 Nov '19

18 Nov '19

Please consider attending the following: MATERIALS ENGINEERING SEMINAR "Void Formation and Evolution in Irradiated Metals Studied by Phase-Field Approach" By Rayaprolu Goutham Sreekar Annadanam Purdue MSE Preliminary Exam Advisor: Professor Anter El-Azab ABSTRACT The safe and efficient operation of nuclear reactors requires the structural materials to be stable chemically, microstructurally and dimensionally under energetic particle irradiation. An ubiquitous phenomenon that occurs in many structural alloys in nuclear reactors is volumetric swelling. This phenomenon is primarily attributed to the nucleation and growth of voids and bubbles filled with transmutation gases such as helium . Early attempts to model this phenomenon involved the use of the classical nucleation theory and reaction rate theory models to capture the nucleation and growth kinetics, respectively, and correlate the observed effects with the irradiation dose rate and temperature. However, these models suffered certain limitations associated with the requirement of homogeneity of the irradiated material and defect fields, and were thus not adequately reliable in explaining the experimental results and in making predictions. Relatively recently, the phase field approach was introduced with the goal to capture the concurrent nucleation and growth of voids and bubbles under the condition of dynamic point defect production by atomic collision cascades in irradiation environments. Of particular interest in this study are the phase field models for void nucleation and growth. In the literature, these models can be primarily classified into two types, those based upon Cahn-Hilliard type equations and others based upon combined Cahn-Hilliard and Allen-Cahn equations. While these models have been well tested, they are not able to provide quantitative predictions yet due to the yet-to-be completed theoretical underpinning of the phase field model parameters, especially the Allen-Cahn mobility. Such parameters require matching with the so-called sharp interface models, which represent the physics of void growth better. In addition to fixing the phase field model parameters, such a matching is also required to guarantee physical and thermodynamic consistency of the phase field approach. In this paper, I review the existing phase field models and discuss further steps to make the phase field consistent with sharp interface theory. Date: Thursday, November 21, 2019 Time: 8:00 A.M. Place: ARMS 1103

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Seminar Notice for Andres Villa Pulido's Ph.D. Final Exam. Monday, Nov. 18, at 10:30 a.m., in ARMS B071
by Son, Rosemary E 16 Nov '19

16 Nov '19

Please consider attending the following: MATERIALS ENGINEERING SEMINAR “Design and Characterization of a PEO-based Polymer Composite Electrolyte Embedded with Doped-LLZO: Role of Dopant in Bulk Ionic Conductivity” By Andres A. Villa Pulido Purdue MSE Ph.D. Final Exam Advisors: Professor E. Ernesto Marinero and Professor David F. Bahr ABSTRACT Ionic conductivity of solid polymer electrolytes (SPEs) can be enhanced by the addition of fillers, while maintaining good chemical stability, and compatibility with popular cathode and anode materials. Additionally, polymer composite electrolytes can replace the flammable organic liquid in a lithium-ion battery design and are compatible with lithium metal. Compatibility with Li-metal is a key development towards a next-generation rechargeable Li-ion battery, as a Li-metal anode has a specific capacity an order of magnitude higher than LiC6 anodes used today in everyday devices. The addition of fillers is understood to suppress the crystalline fraction in the polymer phase, increasing the ionic conductivity, as Li-ion conduction is most mobile through the amorphous phase. A full model for a conduction mechanism has not yet constructed, as there is evidence that a semi-crystalline PEO-based electrolyte performs better than a fully amorphous electrolyte. Furthermore, it is not yet fully understood why the weight load of fillers in PCEs can range from 2.5%wt to 52.5%wt, in order to achieve high ionic conductivity (~10-4S/cm). This work seeks to investigate the conduction mechanism in the PCE through the use of doped-Li7La3Zr2O12 as a filler and analysis of the PCE microstructure. In this work, a solid-state electrolyte, doped-Li7La3Zr2O12 (LLZO) was synthesized via a sol-gel method, and characterized. The effect of doping and co-doping the Li, La and Zr sites in the LLZO garnet was investigated. A PEO-based polymer composite electrolyte (PCE) was prepared by adding bismuth doped LLZO (Li7-xLa3Zr2-xBixO12) as a filler. The bismuth molar ratio was changed in value to study the dopant role on the bulk PCE ionic conductivity, polymer phase crystallinity and microstructure. Results suggest that small variations in dopant can determine the optimal weight load of filler at which the maximum ionic conductivity is reached. By understanding the relationship between filler properties and electrochemical properties, higher performance can be achieved with minimal filler content, lowering manufacturing costs a solid-state rechargeable Li-ion battery. Date: Monday, December 18, 2019 Time: 10:30 A.M. Place: ARMS B071

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Seminar Notice for Andres Villa Pulido's Ph.D. Final Exam. Monday, Nov. 18, at 10:30 a.m., in ARMS B071
by Son, Rosemary E 15 Nov '19

15 Nov '19

Please consider attending the following: MATERIALS ENGINEERING SEMINAR "Design and Characterization of a PEO-based Polymer Composite Electrolyte Embedded with Doped-LLZO: Role of Dopant in Bulk Ionic Conductivity" By Andres A. Villa Pulido Purdue MSE Ph.D. Final Exam Advisors: Professor E. Ernesto Marinero and Professor David F. Bahr ABSTRACT Ionic conductivity of solid polymer electrolytes (SPEs) can be enhanced by the addition of fillers, while maintaining good chemical stability, and compatibility with popular cathode and anode materials. Additionally, polymer composite electrolytes can replace the flammable organic liquid in a lithium-ion battery design and are compatible with lithium metal. Compatibility with Li-metal is a key development towards a next-generation rechargeable Li-ion battery, as a Li-metal anode has a specific capacity an order of magnitude higher than LiC6 anodes used today in everyday devices. The addition of fillers is understood to suppress the crystalline fraction in the polymer phase, increasing the ionic conductivity, as Li-ion conduction is most mobile through the amorphous phase. A full model for a conduction mechanism has not yet constructed, as there is evidence that a semi-crystalline PEO-based electrolyte performs better than a fully amorphous electrolyte. Furthermore, it is not yet fully understood why the weight load of fillers in PCEs can range from 2.5%wt to 52.5%wt, in order to achieve high ionic conductivity (~10-4S/cm). This work seeks to investigate the conduction mechanism in the PCE through the use of doped-Li7La3Zr2O12 as a filler and analysis of the PCE microstructure. In this work, a solid-state electrolyte, doped-Li7La3Zr2O12 (LLZO) was synthesized via a sol-gel method, and characterized. The effect of doping and co-doping the Li, La and Zr sites in the LLZO garnet was investigated. A PEO-based polymer composite electrolyte (PCE) was prepared by adding bismuth doped LLZO (Li7-xLa3Zr2-xBixO12) as a filler. The bismuth molar ratio was changed in value to study the dopant role on the bulk PCE ionic conductivity, polymer phase crystallinity and microstructure. Results suggest that small variations in dopant can determine the optimal weight load of filler at which the maximum ionic conductivity is reached. By understanding the relationship between filler properties and electrochemical properties, higher performance can be achieved with minimal filler content, lowering manufacturing costs a solid-state rechargeable Li-ion battery. Date: Monday, December 18, 2019 Time: 10:30 A.M. Place: ARMS B071

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Seminar Reminder for Xingyao Gao's Ph.D. Final Exam. Monday, November, 18, at 9:00 a.m., in ARMS 3115. "Tunable Multifunctionalities Achieved in Oxide-based Nanocomposite Thin Films"
by Son, Rosemary E 15 Nov '19

15 Nov '19

Please consider attending the following: MATERIALS ENGINEERING SEMINAR "Tunable Multifunctionalities Achieved in Oxide-based Nanocomposite Thin Films" By Xingyao Gao Purdue MSE Ph.D. Final Exam Advisor: Professor Haiyan Wang ABSTRACT Functional oxides indicate the oxides with functionalities, which are recognized as the potential next-generation electronic materials due to their wide variety of crystal structures and properties. Over the past decades, driven by the development of fabrication and device manufacture techniques, more functional oxides with varies applications have been discovered: The biocompatible oxide Al2O3 have been extensively studied in biomedical applications. The ferroelectric oxides with high dielectric permittivities, such as BaTiO3 (BTO), LiNbO3 and Pb(Zr, Ti)O3 (PZT) have been widely used in capacitors, sensors and thermistors. The transparent conducting oxide ZnO and TiO2 have been studied in solar cells. The single-phase multiferroic BiMnO3 and BiFeO3 can be used in data storage devices. The superconducting YBa2Cu3O7 (YBCO) and FeSe have been utilized in high temperature superconductors. The lithium-based oxides LiMn2O4 and LiCoO2 have been extensively studied as the cathode for lithium ion batteries. In this work, we systematically investigated the tunable multifunctionalities in oxide-based nanocomposite thin films. Four first-time reported nanocomposite systems have been demonstrated with vertically aligned nanocomposite or multilayered structures. By controlling the deposition frequency, film composition and the element in the system, tunable ferromagnetic, ferroelectric, multiferroic, magnetotransport and optical properties have been achieved. The multifunctionality study on these oxide nanocomposite thin films has shown great potential in real life applications including nanoscale memory devices, sensors, spintronics, data storage devices etc. Date: Monday, November 18, 2019 Time: 9:00 A.M. Place: ARMS 3115

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Snacks in the Break Room
by Ku Blanco, Aury Y 15 Nov '19

15 Nov '19

Hi all, Your assistance would be appreciated in eating the remaining seminar snacks! Door will be open for another few minutes 😊 Thanks, Aury Ku Administrative Assistant Purdue University School of Materials Engineering Neil Armstrong Hall of Engineering 765/494-4100 akublanc(a)purdue.edu<mailto:staceyl@purdue.edu> [https://www.purdue.edu/brand/images/Purdue_University-150_Years_of_Giant_Le…]

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MSE 690 Tevis Jacobs Nov 15, 3:30 PM, ARMS 1010 (Seeking Tour Guides for 10:45 am)
by Ku Blanco, Aury Y 15 Nov '19

15 Nov '19

Good Morning, Students, Please contact me if any of you are able to help us out with an ARMS Labs tour for Prof. Jacobs today from 10:45 am-11:30 am. Chelsea and I would very much appreciate it! 😊 Forwarding on behalf of Prof. Chelsea Davis, please plan to attend: [cid:image002.png@01D59942.4FBE4AE0] Thank you, Aury Ku Administrative Assistant Purdue University School of Materials Engineering Neil Armstrong Hall of Engineering 765/494-4100 akublanc(a)purdue.edu<mailto:staceyl@purdue.edu> [https://www.purdue.edu/brand/images/Purdue_University-150_Years_of_Giant_Le…]

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Seminar Reminder for Alejandro Figueroa's Preliminary Exam, Friday Nov. 15, at 8:00 a.m., in ARMS 1021 "Irradiation Induced Grain Refinement in Low Temperature U-Mo Metallic Fuels"
by Son, Rosemary E 14 Nov '19

14 Nov '19

Please consider attending the following: MATERIALS ENGINEERING SEMINAR "Irradiation Induced Grain Refinement in Low Temperature U-Mo Metallic Fuels" By Alejandro L. Figueroa Purdue MSE Preliminary Exam Advisor: Professor Maria A. Okuniewski ABSTRACT Uranium molybdenum based fuels are currently being qualified as a replacement for high enrichment fuels, in high performance research and test reactors, as a global threat reduction effort. Irradiation induced grain refinement is currently being investigated in low operating temperature (<0.4Tm) nuclear fuels due to its association to an increase in swelling rates. Uranium molybdenum alloys are of interest due to their accumulation of fission gasses into an ordered nano-bubble superlattice. The superlattice has been observed to suppress the formation of the defect structures typically associated with irradiation induced grain refinement. This behavior limits the ability to correlate the observed mechanisms with historical data. Understanding the underlying mechanisms of irradiation induced grain refinement will aid in fuel performance by tailoring fuel design to suppress the transformation, and accounting for the formation in operating codes. This review discusses the current efforts in characterizing the transformation mechanism, its effect on the microstructure, and modelling of the phenomenon. Date: Friday, November 15, 2019 Time: 8:00 A.M. Place: ARMS 1021

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FW: ULVAC Ellipsometer Demonstration - Nov. 21 @ 1:30pm in BNC1201
by Stacey, Lisa A 12 Nov '19

12 Nov '19

Forwarding on behalf of Jaime Turner, Birck Nanotechnology Center: Lisa Stacey Administrative Assistant to the Department Head Purdue University School of Materials Engineering Neil Armstrong Hall of Engineering 765/494-4095 staceyl(a)purdue.edu [https://www.purdue.edu/brand/images/Purdue_University-150_Years_of_Giant_Le…] ________________________________ [cid:image003.png@01D5994B.CC6892E0] Ron Reger Engineering Manager Birck Nanotechnology Center | Room 2289 | Office: 765.494.6667 | Email: rreger(a)purdue.edu<mailto:rreger@purdue.edu> Wiki: https://wiki.itap.purdue.edu/display/BNCWiki iLabs: https://purdue.ilabsolutions.com/homepage/ ______________________________________________________________ [Purdue_University-150_Years_of_Giant_Leaps.png (300Ã66)] www.purdue.edu/giantleaps<http://www.purdue.edu/giantleaps>

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