Application of Titanium and Titanium Alloys in ship manufacture 

Application of titanium alloys on ships

Titanium and titanium alloys are widely used in nuclear submarines, deep submersibles, atomic icebreakers, hydrofoils, hovercraft, minesweepers, as well as propellers, whip antennas, seawater pipelines, condensers, heat exchangers, acoustic devices, fire fighting equipment.

Titanium pressure shells are mainly used in deep-sea submersibles, and many countries in the world use titanium pressure shells to varying degrees.

The United States' "Sea Cliff" submarine is equipped with a titanium observation module and a control module, and can dive to a depth of 6100m. The United States mainly uses titanium and titanium alloys on ships:

China has also made great achievements in deep submersible technology, and the submersible "Jiaolong" independently designed by China has been submerged to a depth of more than 5,000 m. The titanium and titanium alloys are mainly used on ships in China:

However, only Russia has a large number of titanium on large submarines, and its six "Typhoon" nuclear submarines have industrial pure titanium, Ti64, Ti64ELI, Ti-6Al-2Nb-1Ta-0.8Mo, Ti-3Al-2.5V, IIT-3B, IIT-7M and so on.

01 Nuclear Submarine

Russia is in the international leading position in titanium alloy nuclear submarine research and manufacturing technology, and is the first country to build pressure shells with titanium alloy. During the peak period, the annual output of titanium alloy thick plates and pipes for submarines reached 10,000 tons, accounting for 30% to 50% of the annual output of titanium alloy processed materials. Since the 1960s, Russia has developed four generations of nuclear submarines, the world's first K162 all-titanium nuclear submarine launched in December 1968, has been operating for more than 30 years, to the various oceans, under different loads and environments, there never has been any accident. Russia built the first "ALFA" class nuclear submarine in 1970, and built six in the 1970s and 1980s, each with about 3000t of titanium, the maximum depth of 914m, both light and fast, good mobile performance. A typical example of the use of titanium on ships is the Russian Typhoon class nuclear submarine, which has a titanium shell, because of military needs, the use of double shell structure, its double shell sharing titanium 9000t, so that it has non-magnetic, deep diving, fast speed, low noise, less maintenance and other advantages. The ship is 172.8m long, 23.3m wide, 42.7m high, 232001 water displacement, 33800t diving displacement, stealth speed of 50km per hour, maximum diving depth of 500m, and continuous underwater time of 120 days. The ship, whose construction began in 1977 and which was commissioned in 1981, plays a pivotal role in the Russian Navy.

02 All titanium ship

In 1985, Japan's Tobang Titanium Company and Fujixin Shipbuilding jointly built the "Molizhiten II" all-titanium speedboat, which was very popular in the United States for a period of time. In 1997, the "Titan Fast" speedboat made by Nisho Industrial Company was launched, the length of about 12m, the shape of the hull is a beautiful three-dimensional curve, which can minimize navigation resistance. Eto Shipbuilding in 1998 and 1999 respectively manufactured the "second Asahi Maru" and "Akimaru" two all-titanium ships, the advantages are light weight, fast speed, small engine, less fuel costs, less carbon dioxide emissions, no need for surface coating, adhesion is easy to clean, etc., the disadvantages are high material cost, difficult processing and manufacturing technology, and strict protection requirements. The test results show that the ship speed stability and vibration and noise performance are good.

03 Deep submarine, rescue craft, ship parts

The United States, Japan and France have successively built deep submersible vehicles, using titanium and titanium alloy to make pressure shells. Among them, Ti-6Al-2Nb-1Ta-0.8Mo alloy is used to manufacture the shell of the US Aivin and Sea-Clifi deep-sea submersible; Ti-6Al-4V ELI alloy is used in the buoyancy ball of the French SM97, the United States Aivin, the Japanese "Deep Sea 2000", the United States Navy Deep Sea Rescue boat (DSRV) shell, buoyancy ball, etc.

04 Submersible "Jiaolong"

Jiaolong, China's first independently designed and integrated manned submersible. In July 2010, the sea test of 3759m was completed, and on August 1st, 2011, Jiaolong officially began the submarine operation at a depth of 5180m. That depth means the submersible can reach more than 70 percent of the world's seafloor. "Dragon" design depth is the world's first 7,000 m, the working range covers 99.8% of the global ocean area. China's manned deep diving program is now progressing steadily. Deep-sea submersible is the commanding height of Marine technology development, similar to manned space engineering, reflecting a country's comprehensive technical strength, deep-sea manned submersible activities throughout the continental slope, sea summit, crater, ocean ridge and ocean floor, in the geochemistry, geophysics and Marine biology and other aspects of a large number of research results.

05 Sonar hood

The titanium alloy sonar hood has excellent comprehensive performance and has been applied in the sonar system of Russian ships such as Kursk, Minsk and Kyiv. According to the different requirements of underwater and surface applications, there are basically three kinds of shell plate sound transmission materials selected by the sonar guide hood of Chinese Navy ships in service, one is stainless steel, the other is fiber-reinforced glass steel, and the latest one is titanium alloy.

06 Propeller

Propeller materials require high strength, good fatigue performance in seawater medium, resistance to erosion and cavitation corrosion, and titanium alloy can meet the above comprehensive performance requirements. The United States Navy first used a 1500mm diameter, four-bladed detachable supercavitation titanium alloy propeller on hydrofoils. China developed hydrofoil speedboat propeller in 1972, so far , has produced a diameter of 450~1100mm of various titanium alloy propeller, the maximum can produce a diameter of 1200mm, the mass of 130kg fixed titanium alloy propeller. Long-term use shows that the service life of titanium alloy propellers is more than 5 times that of copper alloy propellers.

07 Ship pumps, valves and piping

The pump, valve and pipe on the ship, due to the very bad working conditions, the pipe made of copper and stainless steel has only 2 to 5 years of life, and the titanium alloy has a good effect after replacement, which is suitable for the high-speed dynamic seawater pipeline. The life standard of Russian ship pipelines stipulates three years, that is, the first time in dock maintenance period (8-9 years); The service life shall not be less than 15 years; All classes of ships should operate reliably for 25 to 30 years.

08 Atomic powered ship

Russia uses titanium alloy instead of stainless steel to manufacture ship steam engines, heat exchangers, coolers, to overcome corrosion damage. Titanium steam engines are widely used in the power plants of existing Russian atomic icebreakers. The use of titanium alloy can extend the service life of its engine by more than 10 times.