Alloy design for the development and production of titanium based bulk metallic glasses

Download

index.pdf

Date

2019

Author

Demir, Iraz Begüm

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

243
views

178
downloads

The bulk metallic glasses (BMGs) are quite new type of metallic alloys exhibiting many superior features like high yield strength, improved elastic behavior, high corrosion resistance and superior abrasion resistance by virtue of its irregular atomic structures. Due to the importance of today’s reduced energy consumption, special attention is given to the light element-based bulk metallic glasses. Among these, Ti-based amorphous alloys have promising mechanical properties for use in engineering applications. Therefore, Ti-based bulk metallic glasses provides a hope as an advanced set of lightweight materials for use in medical applications, defense, automotive and aerospace industries. However, generally Ti-based bulk metallic glasses show poor bulk glass formation that restricts their potential application areas. Studies on this subject will provide an important involvement for the development of glass formation of the Ti based BMGs. In the literature, there are many studies on theoretical and semi-empirical criteria for evaluation of glass forming ability (GFA) of the alloy systems. However, these criteria do not work on every alloy system while providing positive results for some system. Therefore, it is essential to systematically examine the effects of alloying elements for the development of cast metallic glass alloy systems. In this thesis study, besides semi-empirical criteria, with the aim of improvement of the GFA, alloys were synthesized by alloying Ti-Cu binary system with potential candidate alloying elements derived from theoretical predictions by combining the electronic theory of alloys in the pseudopotential approximation which are the part of previous thesis study. As a starting point, Ni, Al and V were selected as alloying elements and correspondingly Ti48Cu30Ni10Al7V5 alloy was produced. After that gradual Si addition was provided on this alloy and Ti47Cu30Ni10Al7V5Si1 and (Ti48Cu30Ni10Al7V5)97Si3 alloys were fabricated to investigate effect of Si as a minor alloying element. Samples of alloys were fabricated by arc melting device equipped with suction casting unit under controlled atmosphere. The effect of the potential alloying elements on the ability to create Ti based BMG was presented by structural and thermal characterization techniques. Atomic 1% of Si addition favored the formation of approximately 40 µm in thickness amorphous structure at the outer zone of the alloy composition Ti47Cu30Ni10Al7V5Si1. Further addition of Si has detrimental effects on glass formation ability. Even at non-equilibrium cooling condition amorphous structure was not observed and the crystallization could not be prevented by copper mold suction casting.

Subject Keywords

Titanium compounds., Ti based BMG, BGFA, Copper mold suction casting

URI

http://etd.lib.metu.edu.tr/upload/12623439/index.pdf
https://hdl.handle.net/11511/43764

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Mechanical properties of Ti6Al4V parts produced by electron beam melting and topology optimization in different building directions Temel Yiğitbaşı, Selen; Konukseven, Erhan İlhan; Gülcan, Orhan; Department of Mechanical Engineering (2018) Titanium and its alloys are used in various industries due to their mechanical properties such as high corrosion resistance, high strength and low-density. However, utilization of parts made of titanium are limited since the lead time for raw material is long, they are hard to machine, and the machining costs are high. On the other hand, it is possible to produce complex parts with powder material by additive manufacturing techniques, and there is a growing interest in research on these new technologies. El...
Nanolayered metallic glass-crystalline composites with high strength and wear resistance Özerinç, Sezer (null; 2020-02-23) Nanolayered metallic glass-crystalline composites are promising materials that combine the high strength of metallic glasses with the superior ductility of crystalline metals. Previous work has focused on metallic glass-FCC crystalline nanolayers, and showed that the strength follows the Hall-Petch behavior of increasing strength with decreasing layer thickness. In our work, we investigated metallic glass-HCP crystalline nanolayers. Interestingly, the strength of these layers does not show any size effect; ...
Titanium-magnesium based composites: Mechanical properties and in-vitro corrosion response in Ringer's solution ESEN, ZİYA; Dikici, Burak; Duygulu, Ozgur; Dericioğlu, Arcan Fehmi (Elsevier BV, 2013-06-20) Ti-Mg composite rods exhibiting both bioinert and biodegradable characteristics have been manufactured by hot rotary swaging from elemental powders of titanium and magnesium. As a result of processing, spherical magnesium powders elongated in the direction of deformation and the dendritic structure in starting magnesium powders transformed into highly equiaxed grains. Magnesium particles in the outer layer of the composites were decorated by thin layer of MgO while the interior parts were free from oxides. ...
Review of magnesium-based biomaterials and their applications Sezer, Nurettin; Evis, Zafer; Kayhan, Said Murat; Tahmasebifar, Aydin; Koc, Muammer (2018-03-01) In biomedical applications, the conventionally used metallic materials, including stainless steel, Co-based alloys and Ti alloys, often times exhibit unsatisfactory results such as stress shielding and metal ion releases. Secondary surgical operation(s) usually become inevitable to prevent long term exposure of body with the toxic implant contents. The metallic biomaterials are being revolutionized with the development of biodegradable materials including several metals, alloys, and metallic glasses. As suc...
Ballistic impact performance of an armor material consisting of alumina and dual phase steel layers Ubeyli, Mustafa; Deniz, Huseyin; DEMİR, TEYFİK; Ögel, Bilgehan; Gurel, Bayram; KELEŞ, Ömer (2011-03-01) Utilization of a ceramic front layer provides an improvement in the ballistic efficiency of monolithic metallic materials. In the current paper, the ballistic behavior of laminated composite having alumina front and dual phase steel backing layers was studied using 7.62 mm armor piercing (AP) projectiles under normal impact. The variables used were martensite content of the backing layer and the areal density of the composite. Experimental results showed that utilization of a 6 mm thick alumina front layer ...

Citation Formats

I. B. Demir, “Alloy design for the development and production of titanium based bulk metallic glasses,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Metallurgical and Materials Engineering., Middle East Technical University, 2019.