Starting from the Stone Age, human beings began to develop ships step by step in order to explore the rivers, lakes and seas. The earliest were rafts and canoes, and later developed into a structure composed of wooden boards and beams. In the 18th century, with the development of metallurgical industry and machinery manufacturing, ships with iron and iron-wood mixed structure began to appear. In the second half of the 19th century, low carbon steel was further used to build ships, and steel became the main material for shipbuilding. With the further development of science and technology in the second half of the 20th century, more and more new materials are used in hull manufacturing. With the continuous advancement of technology, more and more materials can be used to make the hull, and the performance is also continuously improved.
Currently used hull materials include metallic materials and non-metallic materials. Metal materials include steel, aluminum alloy, titanium alloy, etc.; non-metallic materials include wood, cement, composite materials, etc. (This article mainly introduces the evolution and development of ship composites and the application of composite ships in various countries.)
Development history of marine composites
In the mid-40s of last century, the US Navy used composite materials for ship construction for the first time. Since then, it has set off a new chapter in ship construction. Countries around the world have begun to develop various composite ships. The use of composite materials on speed boats, yachts, rowing boats, and small commercial fishing vessels such as trawlers has gradually gained widespread acceptance.
As a new functional structural material, composite materials have light weight, high specific strength and specific rigidity, good damping performance, fatigue resistance, creep resistance, chemical corrosion resistance, good wear resistance, low thermal expansion coefficient, and X-ray permeability The good and other features are highly valued by the shipbuilding industry, especially in terms of manufacturing high-quality hull structures. With the development of society, whether it is used in military, rescue or law enforcement ships, new requirements are placed on the speed of the ship, especially in armed attacks, the weight of the boat must be reduced in order to obtain higher power with the same power Payload, save fuel and reduce costs, while increasing the speed, it also improves the flexibility of the ship's maneuverability. In recent years, advanced composite materials and lightweight structural technologies have developed into key technologies to reduce the weight of the hull.
Composite ship applications in various countries
The United States is the earliest manufacturer of composite ships, and its composite shipbuilding volume currently ranks first in the world. In 1996, the United States-made sea-going boat is a graphite fiber reinforced epoxy resin single-shell structure, which can dive to a depth of 6096m. The ability of the United States to build large composite ships was demonstrated in the MHC project that began mass production of coastal mine-hunting ships in the late 1980s. Stiletto, code-named M80, manufactured in 2006, is the latest high-speed stealth test speedboat. It is the largest hull formed by carbon fiber. Due to the non-welding and riveting process, the overall weight of the ship is greatly reduced, making the speedboat Can easily get a higher speed.
In the early 1960s, Japan became a US yacht contracting and construction base, which laid the foundation for the subsequent construction of composite fishing boats and large boats. By 1993, the number of composite fishing vessels in Japan had exceeded 320,000, and the number of composite yachts exceeded 200,000.
The UK is not only a pioneer country of large composite anti-mine mine ships, it is also a world-class in terms of research and development of composite high-speed craft, and has built many military high-speed craft. In the 1990s, the United Kingdom began to use first-class composite lightweight technology to develop high-speed light hovercraft and HM-2 air ferry. The "Shi Peizheng" Kevlar patrol boat was manufactured, the hull of the boat was 20% lighter than FRP, and nearly 5t less than aluminum alloy. At present, 80% of ships under 20m in the UK are made of composite materials. Thermoplastic composite materials are tough, recyclable, and can shorten the production cycle, making thermoplastic composite materials one of the development directions of lightweight marine composite materials. In recent years, the Plastiki plastic bottle ship in Rothschild, England, in line with the development of biodegradable and recyclable materials, has caused quite a stir. The British VT Halmatic ship manufacturer used the vacuum bag curing process to manufacture a simple thermoplastic bottom vessel DUC, which proves this. It is made of glass fiber/polypropylene material, which achieves perfect weight reduction. This ship has been adopted by the British army. As a Mk6 military assault boat, it was very tough when testing the landing on the beach.
The composite yacht industry in Italy not only developed early, but also has advanced technology. It is one of the centers for manufacturing large luxury yachts over 35m in Europe. The Italian Navy attaches great importance to the development and research of composite anti-mine mineships. In 1967, it began to study novel hard-shell minehunters and successfully developed multi-type Lerici minehunters. Sweden also attaches great importance to the application of composite materials in ships. It should be pointed out that Sweden's sandwich structure composite material technology is world-class, used to build many high-speed military boats and patrol boats, such as TV171 and CG27 coast patrol boats. It is worth mentioning that Sweden developed the world's first composite stealth test boat "Smyge" in 1991. This boat combines advanced composite technology, sandwich structure technology, stealth technology and double-body air cushion technology. High-tech products in ships.
China began trial production in 1958, which opened the prelude to composite shipbuilding. So far, tens of thousands of various composite boats have been manufactured. There are minesweepers with a total length of nearly 39m; fishing vessels are represented by ocean-going fishing vessels of nearly 20m in length built in the mid-to-late 1980s; since 1992, Guangdong has also set off a boom to develop composite high-speed passenger ships. A variety of single high-speed boats, high-speed catamaran hovercraft, motor sailing boats, etc. In 2008, the SD1388 all-composite high-speed boat designed and built by Shenzhen Haysby was successfully launched. This boat with complete independent intellectual property rights has a maximum speed of 70 knots. It successfully interprets the aerospace concepts such as carbon fiber and aramid on the boat, breaking The technology monopoly of a few companies in Europe and the United States has been hailed as a "sea Benz" by the media audience. The HP1500 super high-speed patrol boat developed by Hasbee has become a sizing equipment for China's border enforcement, customs and other maritime law enforcement agencies. It has made outstanding contributions to combating smuggling, protecting national border security, and securing national events, which can be called high-speed and high-performance domestically. A model for the mass construction of composite boats.