The craft's ability to dive so deep is supported by the hull of a titanium alloy, an alloy metal that emerged in the 1950s and has many advantages such as good pressure resistance, corrosion resistance and heat resistance. Titanium alloys have been an important material for rockets, missiles and aircraft bodies since their emergence. Become the metal material with very high universality already. Curiously, however, the titanium alloy used in rockets has never been used in modern submarines. Limited use is also on deep submersibles. Given the environment in which submarines are used, why isn't this metal used in submarines?
To be fair, humans are not without titanium alloy to build submarines, as early as the 1960s, the Soviet Union has been using titanium alloy to build submarines. The Soviet Priest class cruise missile nuclear submarine was the world's first titanium alloy submarine. In 1971, the Alfa class nuclear submarine set a world record of a depth of 900 meters and a speed of 40 water saving. Also depends on the use of titanium alloy boat body. It was, however, the last appearance of a titanium submarine that had not been built since the late 1970s.
The main reason is the high cost, in the 1970s, the Soviet titanium nuclear submarine Komsomolskaya, cost up to $60 billion! The cost is 4 times that of the US Ford class aircraft carrier! And $60 billion was the price then; it would be even more expensive today. Obviously, with Russia's national strength today, it can't afford it at all. Titanium alloy processing has always been a problem in the world, except for argon arc welding and electron beam welding, other welding methods can not be welded. However, argon arc welding and electron beam welding require very high technical requirements of the users, and it is impossible for them to do this job without the old masters. Old masters with this skill are not easy to find, and the pay is not bad.
Besides welding difficulties, cutting of titanium alloy processing also is very difficult, because elastic modulus is too small, cutting of titanium alloy is very damage of cutting tools, to build a titanium alloy submarine, cutting titanium alloy process very much, a set of tools often used only a few times, build a need to constantly change the cutter, it also increases the submarine manufacturing costs. However, as the development direction of future nuclear submarines, titanium alloy submarines are not completely without opportunities. As the technical challenges are solved and the cost of titanium subs plummet, titanium subs are likely to make a comeback as the mainstay of future naval submarines. The submarine weapon will also usher in greater development opportunities and become the country's heavy weapon besides aircraft carrier.
