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Development of Iron-Rich Nanocrystalline Magnetic Materials to Minimize Magnetostriction for High Current Inductor Cores

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Development of Iron-Rich Nanocrystalline Magnetic Materials to Minimize Magnetostriction for High Current Inductor Cores DEVELOPMENT OF IRON-RICH (FE1-X-YNIXCOY)88ZR7B4CU1 NANOCRYSTALLINE MAGNETIC MATERIALS TO MINIMIZE MAGNETOSTRICTION FOR HIGH CURRENT INDUCTOR CORES By ANTHONY MARTONE Submitted in partial fulfillment of the requirements For the degree of Master of Science Thesis Advisor: Dr. Matthew Willard Department of Materials Science and Engineering CASE WESTERN RESERVE UNIVERSITY August 2017 CASE WESTERN RESERVE UNIVERSITY SCHOOL OF GRADUATE STUDIES We hereby approve the thesis of Anthony M Martone candidate for the degree of Master of Science*. Committee Chair Professor Matthew Willard Committee Member Professor David Matthiesen Committee Member Professor Alp Sehirlioglu 30 June 2017 *We also certify that written approval has been obtained for any proprietary material contained therein. Table of Contents 1. Acknowledgements ................................................................................................... 11 2. Abstract ...................................................................................................................... 12 3. Introduction ............................................................................................................... 13 1. Technological Demand for New Magnetic Core Material ................................................. 13 2. Magnetic Material and Properties ..................................................................................... 14 2.1: Inductor Magnetic Core Properties ................................................................................. 14 2.2: Coercivity and Grain Size ................................................................................................. 17 2.3: Microstructure of Nanocrystalline Magnetic Alloys ....................................................... 19 2.4: Magnetostriction in Nanocrystalline Magnetic Alloys .................................................... 20 3. Alloy Design ........................................................................................................................ 22 3.1: Alloy Design Overview ..................................................................................................... 22 3.2: Alloy Design Paths ........................................................................................................... 22 4. Experimental Procedure ................................................................................................ 25 1. Experimental Overview ...................................................................................................... 25 2. Alloy Processing ................................................................................................................. 26 3. Characterization of Ribbons ............................................................................................... 28 3.1: As-Spun Ribbon X-Ray Diffraction ................................................................................... 28 3.2: Differential Scanning Calorimetry ................................................................................... 28 3.3: Heat-Treated Ribbon X-Ray Diffraction .......................................................................... 29 1 3.4: Room Temperature Magnetic Hysteresis ....................................................................... 30 3.5: Magnetostriction Characterization ................................................................................. 31 3.6: Thermomagnetic Characterization ................................................................................. 37 5. Results and Discussion ................................................................................................. 38 1. Structural and Thermal Analysis ........................................................................................ 38 1.1: X-Ray Diffraction Overview ............................................................................................. 38 1.2: Structural Analysis: As-Spun Ribbon ............................................................................... 39 1.3: Thermal Analysis: As-Spun Ribbons ................................................................................ 40 1.4: Structural Analysis: Heat-Treated Ribbons ..................................................................... 43 2. Magnetic Property Analysis ............................................................................................... 49 2.1: Magnetic Analysis Overview ........................................................................................... 49 2.2: Magnetic Hysteresis ........................................................................................................ 49 2.3: Magnetostriction ............................................................................................................ 53 2.4: Thermomagnetic Characterization ................................................................................. 54 2.5: Discussion of Magnetic Property Relations ..................................................................... 57 6. Future Work .................................................................................................................. 64 1. Multivariate Regression of Magnetostriction .................................................................... 64 1.1: Multivariate Regression Overview .................................................................................. 64 1.2: (Fe,Ni,Co)88Zr7B4Cu1 Analysis ........................................................................................... 64 1.3: (Fe,Ni,Co)86Zr7B6Cu1 Analysis ........................................................................................... 67 2 2. Nanocrystalline Magnetic Powder ..................................................................................... 70 7. Conclusion .................................................................................................................... 71 Appendix ........................................................................................................................... 72 1. Experimental Procedure ........................................................................................................ 72 3. Magnetic Analysis .................................................................................................................. 86 4. Future Work ........................................................................................................................... 87 5. Nanocrystalline Magnetic Powders ....................................................................................... 97 References ....................................................................................................................... 107 3 List of Tables Table 1: Alloy compositions (atomic %) created and analyzed ....................................... 26 Table 2: Onset and peak crystallization temperatures of primary (Tx1) and secondary (Tx2) crystallization for (Fe,Ni,Co)88Zr7B4Cu1 as-spun samples at 10 K/min DSC scan .......... 42 Table 3: Lattice parameter (ao) and crystallite sizes (D) of ribbons annealed at 550°C for 3600 s ................................................................................................................................ 48 Table 4: RT hysteresis properties (saturation specific magnetization, Ms, and coercivity, Hc) of (Fe,Ni,Co)88Zr7B4Cu1 as-spun ribbons .................................................................. 53 Table 5: RT hysteresis properties (saturation specific magnetization, Ms, and coercivity, Hc) of (Fe,Ni,Co)88Zr7B4Cu1 ribbons annealed at 550°C for 3600 s ............................... 53 Table 6: Magnetostrictive coefficients, λ, for (Fe,Ni,Co)88Zr7B4Cu1 as-spun and 550°C annealed for 3600 s ribbons .............................................................................................. 54 Table 7: Summary of structural (crystallite size, D) and magnetic properties (saturation specific magnetization, Ms, coercivity, Hc, and magnetostriction coefficient, λ) of nanocrystalline (Fe,Ni,Co)88Zr7B4Cu1 alloys annealed at 550°C for 3600 s .................... 56 Table 8: Various alloys compositions with predicted zero magnetostriction in (Fe,Ni,Co)88Zr7B4Cu1 nanocrystalline alloy systems based on multivariate regression .. 67 Table 9: Various alloys compositions with predicted zero magnetostriction in (Fe,Ni,Co)86Zr7B6Cu1 nanocrystalline alloy systems based on multivariate regression ... 69 Table 10: Sensitivity, accuracy, and model information for equipment and instruments used for alloy production and analysis.............................................................................. 72 4 Table 11: Pictures of all equipment and instruments used for alloy production and analysis .............................................................................................................................. 74 Table 12: Crystallite size determined from each peak for (Fe,Ni,Co)88Zr7B4Cu1 alloys annealed at 550°C for 3600 s ............................................................................................ 85 Table 13: Magnetostriction, λ, data of FexNiyCo88-x-yZr7B4Cu1 nanocrystalline alloy 1,10, 29 systems used for multivariate analysis ..................................................................... 87 Table 14: Magnetostriction data, λ, of FexNiyCo86-x-yZr7B6Cu1 nanocrystalline alloy 29 systems used for multivariate analysis from Muller 2000 ............................................. 88 Table 15: Processing
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