Titanium and its Alloys: Processing, Fabrication and Mechanical Performance

Abstract

Titanium alloys have excellent mechanical properties and corrosion resistance. However, annual global titanium is dwarfed by commodity metals. This is in part due to the current primary production method which requires a complex discontinuous reduction route in addition to several costly downstream processing steps to convert titanium sponge into usable product for aerospace and aircraft components. The processing routes from vacuum arc remelting to downstream forging and extrusion are discussed in detail for titanium alloys. Casting and powder metallurgy (PM) routes are also described for near net shape products and cost savings. A wide range of post processing fabrication routes are presented, including welding, superplastic forming/diffusion bonding, and the most costly fabrication step, machining. Emerging additive manufacturing techniques are also included in this chapter. Finally, the effects of prior processing and resultant alpha and beta morphology on the mechanical performance, including tensile strength, ductility, fatigue, fracture toughness, and creep are covered in detail.

Corrosion behaviour of Ti‐Al‐xV‐yFe experimental alloys in 3.5 wt% NaCl and 3.5 M H2SO4

“…Titanium alloys are very important engineering materials due to their attractive properties such as high specific strength, good corrosion resistance in most industrial environments and excellent biocompatibility . These properties have made the alloys suitable for use in a wide spectrum of applications including the aerospace industry where stringent requirements have to be met and other land‐based applications such as marine, sports, chemical, automotive, jewelleries and biomedical industries …”

Validation and optimization of cutting parameters for Ti-6Al-4V turning operation using DEFORM 3D simulations and Taguchi method

“…Ti-6Al-4V, an a + b titanium alloy remains the most studied and most utilised titanium alloy. It is amenable to different heat treatments or thermomechanical treatments which do not only manipulate its phase constituents but yield a good combination of mechanical properties [1][2][3]. The balanced combination of corrosion resistance, biocompatibility and mechanical properties exhibited by this alloy makes it potentially attractive for a wide range of applications [4,5].…”

“…Hence, high cost has been the main impediment to the widespread use of titanium alloys [9]. The high cost of production of titanium alloys is due to several factors including difficult extraction process due to affinity for interstitial elements, use of expensive alloying elements such as vanadium, molybdenum, niobium and tantalum, multi-stage forging involving up to forty steps and difficult machining [2,10]. Of these factors, machining has been reported to be the most significant as it accounts for 40% of the total cost of making finished titanium components and up to 90% loss of material is incurred during the process [7,11].…”

FAST-forge of Titanium Alloy Swarf: A Solid-State Closed-Loop Recycling Approach for Aerospace Machining Waste

“…Due to the high strength-to-weight ratio, corrosion resistance, and excellent fatigue properties of titanium alloys, they are widely used in the aerospace sector in airframe forged parts, landing gear forgings and aero-engine compressor components [1]. There is predicted to be a doubling of global air traffic in the next 15 years, with a requirement for over 39,000 passenger and freight aircraft over the next 20 years [2].…”