Titanium industries - one metal, a thousand possibilities
Titanium industries is the sector that employs personnel, equipment and technology in order to deliver pure (or alloyed !) titanium metal for use in different commercial and industrial products - Boeings, space shuttles, golf clubs, sporks, etc. The size of this industrial sector it’s difficult to estimate due to the different uses of titanium and, more importantly, the form in which titanium is used commercially. As for the titanium metal, it is estimated that as of 2009, the global production capacity for
titanium sponge
is about 220000 tons per year.
Titanium is particularly expensive to refine, process, and fabricate. In terms of processing cost per cubic inch, titanium refining is as five times more expensive as aluminum, and as much as ten times regarding forming into ingots and subsequent fabrication into finished products. Improved and cheaper tehnologies of producing titanium are explored currently in titanium industries, the most advanced being the FFC Cambridge process used to obtain
titanium metal powder
The initial step of the titanium production cycle in titanium industries is the extraction of titanium ore by
titanium mining
This is not a particularly expensive or complicated process as it usually happens on surface without employing deep mining operations, with the commercial titanium ores being available as a component of mineral sands.
Mined titanium ore usually takes two possible routes in its long and (did I mentioned it already?) expensive way of becoming pure titanium. The first one, and 95% of the mined titanium ore goes this way, is further refining in order to be marketed as pure titanium dioxide used in coating, plastic, printing ink, paper sheet, chemical fiber, daily chemical, medicine and sometimes even food.
Commercial titanium dioxide is produced by either the sulfate process or the chloride process. The sulfate process yields anatase and rutile forms of titanium dioxide, where the chloride process form only yields the rutile form. Briefly, in the sulfate process, titanium ore is dissolved in sulfuric acid and the product is diluted with water or dilute acid. Similarly, the chloride process involves the titanium-containing mineral being reacted with concentrated hydrochloric acid to form solutions of titanium (IV) chloride which are then further purified. Hydrolysis of the tetrachloride will yield the dioxide which is filtered off, washed, and packaged.
The second main titanium ore possibility of refining in titanium industries is with the intention of obtaining commercially pure titanium metal. This is achieved through the Kroll process, by converting titanium dioxide bearing titanium ore into chloride thus creating titanium chlorides. These are chemicals separated through a process called fractional distillation, with the final product being a porous mass of titanium metal mixed with byproducts, known as titanium sponge. This sponge is then subjected to leaching or heated vacuum distillation to remove further impurities.
Titanium sponge, often mixed with titanium scrap, is melted into ingots, which undergoes primary fabrication processes, such as rolling and forging in order to produce titanium mill products such as
titanium plates
or
titanium foil
and billet or bars.
Secondary fabrication processes are used to manufacture titanium parts and components from titanium mill products. Fabrication is the most costly producing, with
machining titanium
and
titanium extrusion
being among the most difficult to master.
Titanium secondary fabrication is the primary source of titanium scrap that is fuelling the
titanium recycling
sector. Although the melting of titanium scrap poses some additional challenges, the sheer value of the metal, combined with the large quantities that are discarded in the fabrication process, is making it economically efficient. The current evaluations of the titanium market are circling around two billions dollars worldwide.
Further assembly of titanium components and products involve
welding titanium,laser welding titanium
being the preferred method due to the superior results that are obtained regarding strength and unmodified characteristics of the metal. For low strength requirements,
brazing titanium
technologies are also used, having the advantage of evading the problems associated with titanium high reactivity with oxygen.
