Process Piping Materials – Module 2 – M06-036

2.11.Titanium

Titanium offers extreme resistance to corrosion of salt water and marine environment with exceptional resistance to wide range of acids, alkalis and chemicals. The corrosion resistance of Titanium is due to a stable, protective, and strongly adherent oxide film layer. This film forms instantly when a fresh surface is exposed to air or moisture. This film growth is accelerated under strong oxidizing conditions. The Titanium oxide film is capable of healing itself instantly in the presence of moisture or oxygen.

•Characteristics

−Highest strength-to-weight ratio of any metal.

−About 20 times more erosion resistant than the copper nickel alloys.

−Excellent erosion resistance; permits use of higher pipeline velocities. Due to its high heat transfer efficiency and higher strength, thinner wall tubes can be used.

−Commercially pure or unalloyed Titanium is available in ASTM Grades 1 through 4 and 7; grade 1 being most pure.

−Titanium has high affinity to oxygen – strong deoxidiser.

−Excellent corrosion resistance due to a presence of a protective thin oxide surface film. Can be used as biomaterial.

−Can be used in elevated temperature components. It maintains corrosion resistance even at high temperatures with maximum limit at 2000°F/1095°C. Brinell hardness is about 215.

−Limitation of pure Ti is its lower strength. Alloying is done to improve strength.

−Can catch fire and cause severe damage.

•Applications

−The corrosion resistance of Titanium in chlorine gas and chlorine containing solutions is the basis for a large amount of Titanium applications.

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