Titanium

Titanium (Ti) is a soft, ductile, lightweight silvery grey metal that has a very very high tensile strength, which gives it one of the best strength to weight ratios - but it has a poor compressive strength. It is notable as one of the most biocompatible metals as it is not harmful or toxic to living tissue. It is resistant to corrosion because in oxygen it naturally forms a protective oxide film, making it resistant to corrosion also in bodily fluids.

Titanium ore was first discovered in the late 1700's by an English clergyman on Cornish beach sands, and later named after Titans in Greek mytholoy by a German chemist. It is the fourth most abundant structural metal on Earth with primary ores of ilmenite, leucoxene, and rutile as well as anatase, perovskite, and sphene. Today the top exporters of Titanium are South Africa, Australia, Norway, Mozambique, and Sierra Leone, where half the Titanium mined comes from river sediments or alluvial deposits formed by rivers as they reach the sea. It is extracted through a process of dredging or dry mining.

Negative impacts of mining are generally land-use changes such as deforestation, erosion, alteration of soil profiles, streams and wetlands as well as noise and dust pollution. However because titanium does not degrade it is 100% recyclable and currently around 90% of titanium is recycled via processes that require significantly lower water and energy use than it takes to process the metal from its virgin ores.

The three main markets for titanium metals are in aerospace, non-aerospace industries, and alloy additives. The manufacture of gas turbines accounts for almost half of the annual titanium production, whilst many aircraft frames include titanium alloys because of the weight to strength ratios. Likewise Titanium is an important material for medical prosthetics such as hip-joint replacements because of its weight and strength but also because of its resistance to corrosion even in the human body. It is also used to manufacture anodes in electrolytic solutions because of corrosion resistance, in building servicing products such as diffusers, filtration pumps, heat exchangers, valves, as well as watches, tools and knives.

In the UK construction industry, titanium's use is limited compared to other metals like steel or aluminium due to its higher cost, however, it is increasingly selected for high-end applications where its superior properties justify the expense:

• Titanium is used in architectural cladding for building exteriors, particularly in high-profile structures where a sleek, modern look is desired. Its natural resistance to environmental factors like pollution and saltwater makes it ideal for coastal areas.
• Similar to cladding, titanium is used in roofing systems, especially for buildings that require long-lasting materials. It is particularly beneficial in situations where the roof needs to withstand harsh weather conditions without significant maintenance.
• Titanium is sometimes used in structural components where strength, lightweight, and resistance to corrosion are critical. Although less common than steel or aluminium, its use is growing in specialised applications.
• Due to its strength and lightweight properties, titanium is occasionally used in the frames of large windows and curtain walls. This allows for the creation of large, unsupported glass areas while maintaining structural integrity.
• Titanium bolts, nuts, and other connectors are used in construction projects, particularly where exposure to moisture or corrosive environments is a concern, such as in bridges or coastal buildings.
• Titanium is sometimes used in decorative elements like façade features, sculptures, or other architectural details due to its unique colouration and ability to form natural oxide layers that change colour under different lighting conditions.
• Given its excellent resistance to seawater, titanium is used in structures such as piers, jetties, and other coastal or offshore constructions where long-term durability against corrosion is essential.

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• Decorative metal ceilings.
• Failure of metals.
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• Guidance for construction quality management professionals: Structural Steelwork.
• Metal.
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