The service life of ERP ship is 7 to 8 years, the legal service life of wooden boat is 5 years. Steel and aluminum ship is 9 years. The titanium metal’s salt water and river water corrosion can be compared with the platinum. Therefore, it can be said that the design of semi permanent plate’s thickness does not need to consider the corrosion and thinning. It is inferred that from the actual results of the investigation the legal service life of the titanium ship is much longer than that of the steel and aluminum. Titanium has small density and good corrosion resistance, high strength, good seawater corrosion resistance, mechanical processing, welding performance, and does not need to heat treatment after welding. It has a broad prospect as a marine material. Although the current usage of titanium is very small, it already has a case of the titanium ship, and get a very high evaluation. In the future, titanium industry should make great efforts to reduce the cost of titanium and processing costs, and actively edit the titanium standard design and processing and shipbuilding skills to promote the applications of titanium.
It has not been more than 100 years, but the titanium plate is very rich in resources, the TiO2 form exists in the ore, its reserves take its place after the AIFeMg and rank the fourth place. The earliest titanium vessel is the primary attack submarine in the former Soviet Union made in 1978 -- 1983. It is presumed that this submarine’s pressure hull is made of titanium and its water displacement is 2800t, the drainage amount under the water is 3600t and the depth of diving is 600m. The competitive speedboat is the earliest titanium ship created by Toho Co. Ltd and rattan new shipyard and it was launched in May 1985 and registered in the foreign. The length of this speedboat is 17m, the width is 4m, the height is 2.5m and the weight is 2.8t. In addition to the cabin with steel, the other parts from the frame to the hull are all made of titanium. According to the necessary strength calculation, the bottom of the ship selected 4mm -- 15 mm thick titanium plate, the deck selected 2.5mm thick pure  titanium plate and the ladder, steering wheel and axial rudders are also made of titanium rod.