MSc. Thesis Defense:Onur Zırhlı

MSc. Thesis Defense:Onur Zırhlı

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DEVELOPMENT OF A NOVEL METHOD TO OBTAIN COMPLEX SHAPED MAGNETIC STRUCTURES FOR ADDITIVE MANUFACTURING

 

Onur ZIRHLI
Materials Science and Nano Engineering, MSc. Thesis, 2019

 

Thesis Jury

Assoc. Prof. Dr. Burç Mısırlıoğlu (Thesis Advisor), Assoc. Prof. Dr. Ozan Akdoğan (Thesis Co-Advisor), Prof. Dr. Melih Papila, Assoc. Prof. Dr. Özge Akbulut, Asst. Prof. Dr. Ali Fuat Ergenç

 

 

Date & Time: 18th July 2019 – 13:00 AM

Place: FENS G032

Keywords : additive manufacturing, 3d printing, hard magnet, magnetism, rare-earth free magnet, pulse magnetizer, ball milling, nitridation

 

Abstract

 

Hard magnetic materials play a critical role in numerous industrial areas related and limited to magnetic tapes, hard drive units, speaker drivers, biomedical measurement devices, electric motors, hybrid cars, wind turbines and sensors. Since such applications include large scale manufacturing, size and cost of the magnetic material has a direct effect on it. Magnetic energy density and availability of a magnetic material are main characteristics that concerns size and cost effectiveness in a large scale application.

Today, neodymium iron boron (NdFeB), aluminum nickel cobalt (Alnico), and ferrite are mostly used as magnetic materials. NdFeB is the most significant one among them because of its magnetic energy density. However, there is shortage of these materials when it comes to providing rare-earth materials. Moreover, in consequence of environmental concerns, there are regulations that limit NdFeB supply. These are the main reasons that the industry is in search for new, rare-earth free magnetic materials. Among these, a metastable iron nitride phase, Fe16N2 has been theoretically proven to shows promising magnetic properties in literature and become prominent as possible alternative to NdFeB.

In this study we propose a possible solution to the aforementioned problems by establishing a method to synthesize Fe16N2 particles using ball milled iron micro/nano particles and tried to utilize it in additive manufacturing. Prepared Fe16N2 particles were characterized by XRD and SEM analysis before any further processing. Additive manufacturing is an effective method to fabricate sophisticated geometries with added functionalities such as magnetic parts possessing complex geometries. Furthermore, we also attempted to increase the anisotropy in addition to the magnetic energy density of the printed material by manipulating it with a pulse magnetizer circuit. During the course of the work, we also undertook preparation of Fe16N2, in thin film form and characterize it via the in-house built magneto optical kerr effect (MOKE) system. The latter setup was optimized using ball milled NdFeB and iron flakes to show the proof of concept and setup functionality.