Manufacturing and Failure Analysis of Titanium Alloys

Titanium, described as the metal of the 21 st Century, is a lustrous white metal with an atomic number of 22. It belongs to the 'Transition Metal' group in the Periodic When you watch the launch of a space shuttle or satellite, you are watching tons of titanium being shot into space. The US Space shuttle structure is 85 % titanium! It is used extensively by the aerospace industry because of its high strength, light weight, and its ability to withstand high temperatures. Re-entry could not be possible without titanium. The new 'Dreamliner' Boeing 787 uses titanium to the extent of 15 % of its weight. Besides aerospace, titanium finds wide-spread use in the military, medical equipment, atomic energy, high technology applications, and in consumer goods. Titanium is the 4 th most abundant metal and 9 th most abundant element in the earth's crust.

Pure titanium melts at 1670 • C and has a density of 4.51 g cm −3 .

As the era develops and the demand of the technology is compulsory, materials that been extracted from inside the earth is not enough to compensate it. Such as alloys, the demand of alloys that is capable to be used in extreme condition and environment is highly inclining nowadays. The usage of superalloys which is based form nickel and cobalt is one of the option for extreme environment. However, these alloys is unable to balance the growing technologies that have been developed due to they have very high weight and heavy in order to increase their strength.

Due to continuous increase in fuel price automobile manufacturers are switching to light weight materials. Titanium (Ti) is superior in terms of strength and density when compared with currently used materials in automobiles. This paper highlights distinct properties of Titanium over those materials. Latest cost effective machining methods and major applications of Titanium automobile parts are mentioned in subsequent pages

2017

This paper provides a classification of titanium and titanium alloys associated with their chemical composition and structural state after annealing. Described are their physical, mechanical and technological properties. A short analysis of areas of application of these materials is made.

Titanium Alloys - Novel Aspects of Their Processing [Working Title]

Journal of Nuclear Materials, 2013

Using theoretical quantum chemical methods, we investigate the dearth of ordered alloys involving thorium and titanium. Whereas both these elements are known to alloy very readily with various other elements, for example with oxygen, current experimental data suggests that Th and Ti do not alloy very readily with each other. In this work, we consider a variety of ordered alloys at varying stoichiometries involving these elements within the framework of density functional theory using the generalized gradient approximation for the exchange and correlation functional. By probing the energetics, electronic, phonon and elastic properties of these systems, we confirm the scarcity of ordered alloys involving Th and Ti, since for a variety of reasons many of the systems that we considered were found to be unfavorable. However, our investigations resulted in one plausible ordered structure: We propose ThTi 3 in the Cr 3 Si structure as a metastable ordered alloy. 1 I. INTRODUCTION Thorium, a heavy metal, combined with various elements such as boron, carbon, nitrogen and oxygen has been studied both theoretically 1-3 and experimentally 4-6 in relation 2 to a range of physical, chemical, electronic, and thermophysical properties, often exhibiting high density, good thermal conductivity and good mechanical properties. The applications of Th-based alloys are wide-ranging. These include uses in nuclear reactors and in the aerospace industry because of its good corrosion resistant properties and high melting points. Th binary systems exist in various ordered alloys such thorium monocarbide (ThC), 7 mononitride (ThN) 8 and monoxide ThO. 9 ThO crystallizes in the rock salt structure, while ThO 2 crystallizes in the fluorite structure. ThB 4 10 and ThB 6 exist in the ThB 4 and CaB 6 structures. Titanium, a relatively light metal is strong, has excellent corrosion resistant properties and a high melting point. Given its relatively small atomic size, Ti can be easily impregnated into materials without radically altering the host crystal structure. Therefore, Ti is a versatile element for alloying and modifying the properties-especially the strength properties-of materials. Applications range from additives in paints to metals for aerospace and industry. In this way, Ti is useful for engineering the properties of materials. Ti-based oxides are very well known, for example TiO 2 exists in the equilibrium rutile, and the metastable anatase and brookite structures, and the high pressure monclinic and orthorhombic forms. Ti also combines very readily with other metals, such as Pt in a variety of crystallographic forms and stoichiometries. It would seem, then, that ordered alloys involving Th and Ti should form readily when in fact this is not the case. Experimental evidence by Carlson et al. 11 dating back to 1956 still appears to be the only authoritative view on this subject, although similar results were found by Pedersen et al. in 1980. 12 Carlson et al. discovered that Th-Ti forms a simple eutectic at 1190 o C and at 12 wt % Ti, with no intermediate phases. Pedersen et al. found the eutectic composition to be 13.26 wt % Ti. The solid phases at the eutectic are α-Th (cubic) and β-Ti (hexagonal). Carlson et al. concluded that solid solubilities at room temperatures are negligible. They argued that since the atomic radii of Th and Ti differ by about 22%, and because the Hume-Rothery rules for alloying suggest that extensive solid solubility should not occur between metals differing in size by more than 15%, the dearth of compounds (ordered or not) should not be surprising. Furthermore, they argued that since there is a marginal difference in the electronegativity of these two elements (the electronegativities are 1.3 for Th and 1.5 for Ti), compound phases should not form readily.

Defect and Diffusion Forum, 2018

Since the development of the Ti54M titanium alloy in 2003, its application within the aerospace sector has gradually increased due to the combination of properties such as improved forgeability and machinability, low flow stress at elevated temperatures, and superplastic characteristics. However, for the successful exploitation of Ti54M a comprehensive understanding of its mechanical characteristics, microstructure stability, and superplastic behaviour is required. The superplastic forming of titanium alloys is characterised by high deformation at slow strain rates and high temperatures which influence the material microstructure, and in turn, determine the forming parameters. These mechanisms make the prediction of the material behaviour very challenging, limiting its application within the aerospace industry. Even though Ti54M has been commercially available for over 10 years, further studies of its mechanical and superplastic properties are still required with the aim of assessin...

Metals, 2021

The invited review paper to accompany this special issue, authored by Williams and Boyer [...]