According to the statistics of China Iron and Steel Industry Association, the domestic market share of domestic steel products has continued to increase in 2010. The output of key steel products such as automotive steel, pipeline steel, silicon steel, ship plates, and rails has increased significantly, and 18 of the 22 major steel types The domestic market share of steel has reached over 95%, and all high-speed rails with a speed of 350 kilometers per hour have been domestically produced.
Chinese warships and carrier submarines all need special steels, and these are banned from China by the United States and Japan. Chinese domestic aircraft carrier steels are domestic special steels.
1. Automotive steel;
The industry with the largest amount of special steel is the automotive industry.
Such as crankshaft, non-quenched and tempered steel for connecting rods. Case hardened steels for transmission gears, CVT flywheels, etc. have been domestically produced. One of the most used steel types in special steel is stainless steel. MGJT's nuclear power stainless steel has also been localized.
2. Special steel for thermal power;
In the 1960s, the development of China's thermal power special steel at that time was world-leading.
Lu Yanzhang and Liu Rongzao's team developed G102 steel. In the 1970s, Liu Rongzao's team developed G106 steel, which was ahead of the world. The American V.K.Sikka team developed T91 steel on the basis of G102.
Currently, T / P92, T / P91, T / P122, TP347HFG, Super304H, HR3C, etc., which are mainly used in thermal power, are used in thermal power.
BWJT Special Steel Group realizes the domestic production of various steel pipes for 600 ℃ ultra-supercritical thermal power units, all of which are high-grade oriented silicon steel, forming its core patented technology.
Rolling of 5mm diameter high carbon steel wire rod produced by AGJT Group has been completely successful. Shougang has produced X80-class ultra-thick pipeline steel coils.
3, high-speed rail wheels;
High-speed EMU wheels are the highest-end products in wheel products, and currently only a few countries in the world can produce them.
MGJT Special Steel Group has achieved breakthroughs in key technology for EMU wheels. The independently developed Chinese standard EMU wheels and axles with a speed of 350 kilometers per hour have achieved all relevant technical requirements. The EMU D2 powered wheels and EMU D2 non-powered wheels produced by Maanshan Iron and Steel Co., Ltd. successfully passed the CRCC product certification.
China Iron & Steel Research Institute develops and produces a new type of high-speed rail wheel steel (HS7) that meets the standards for steel for high-speed rail wheels based on the ultra-pure and homogeneous smelting platform.
Through purification technology, solidification control technology and uniform diffusion technology, the purity and microstructure uniformity of the test materials have reached the international advanced level. It has excellent hardenability, delay cracking and abrasion, and resists peeling on the tread. A number of indicators exceed similar imported materials of high-speed wheels of 300 kilometers per hour, especially the material's impact toughness at room temperature and low temperature is 3-5 times higher than the standard, which is significantly higher than similar high-speed wheel materials at home and abroad.
4. Arches and cables, gears, gearboxes, transmission shafts, and oil rigs for large bridges in China.
The 24 giant gates in the Three Gorges Permanent Ship Lock, the steel of BWJT and AGJT Special Steel Group are also used in the pressure steel pipes and volutes of hydro-generator units.
The steel used in nuclear power equipment, such as main pipelines and steel containments, is also domestically produced. Turbine generator rotors, nuclear power pipe fittings, tank armor, tracks, gun tubes, submarine shells, warship hulls, aircraft carrier decks, arresting cables, 9Ni steel for LNG ships, etc. are all special steels, all made in China.
5, Chinese submarine steel;
China's high-strength steel technology as early as the 1960s and 1970s fully met the needs of hull materials for nuclear submarines.
The yield strength of the nickel-free chromium 909 steel, low nickel chromium 904 steel and nickel chromium 921 steel developed at the time in China all reached 590 MPa, exceeding the 550 MPa of HY-80 steel used in nuclear submarines in the United States at that time.
China's research on non-magnetic steel for ships has also succeeded. A low-magnetic steel has been used in destroyers, shells of minesweepers, magnetic compass walls of submarines, and structural components of degaussing docks.
6. The success of China's microcrystalline steel (super steel) proves that China is a huge breakthrough in the use of special steel technology, leading the United States, Japan and Russia.
In August 2017, the world's top academic journal "Science" magazine article: China successfully developed a "super steel" with a yield strength of 2200 MPa (megapascals) and achieved mass production.
The submarine keel and the carrier deck require very high steel strength. The US aircraft carrier uses 690MPa-grade high-strength steel as the carrier deck steel. The latest HSLA115 steel has a strength of 785MPa.
Submarine pressure shell steel, US 3HY100 steel. HY130 steel. HSLA100 steel has a maximum strength of 900MPa, which is used as a strategic material by the US government to restrict exports.
The strength of NS110 steel in Japan reaches 1080MPa, which is a little lower than the 1100MPa steel developed by China's BWJT Special Steel Group in 2008; the highest strength of Russia's АБ series steel reaches 1175MPa.
In 2011, BWJT Special Steel Group broke through the production capacity of special steel with a yield strength of 1100, marking that China's submarine steel has entered the world's leading ranks.
Today, China's super-steel has reached 2200 MPa and has been mass-produced, giving priority to meeting military needs.
China Super Steel has been successfully developed and scaled up for industrial production, mainly by the team of Professor Luo Haiwen of the University of Science and Technology Beijing.
Professor Luo Haiwen used his accumulated experience in successfully developing the third-generation automotive manganese steel to break through the problem of super steel development.
For special steels, either it has a high yield, but the ductility is relatively weak, or it has excellent ductility, but the yield is not strong enough. It is difficult and difficult to have both.
Professor Luo Haiwen of the University of Science and Technology Beijing has successfully developed a super steel with high yield and high ductility. The most critical problem was successfully overcome.
In order to verify the authenticity of Chinese super steel, scientists at the Massachusetts Institute of Technology also performed material characterization technology verification on Chinese-produced super steels. The verification results finally confirmed that Chinese-produced super steels were indeed published by Professor Luo Haiwen in Science. The paper in the magazine said that.
The newly invented super steel has achieved an unprecedented yield strength of 2,000 MPa and a uniform elongation of 16%, "having the best combination of strength and ductility".
The steel has two major advantages:
1) Low cost. This super steel is a simple medium manganese steel composition system containing 10% manganese, 0.47% carbon, 2% aluminum, and 0.7% vanadium. These are common alloying elements in steel materials that are widely used today. It does not improve the toughness by using a large amount of expensive alloying elements;
2) The steel is prepared through processing techniques widely used in the industry, such as hot-rolled, cold-rolled, and heat-treated conventional industrial preparation processes, not special processing processes that are difficult to scale to industrial production. Therefore, this kind of super steel has the potential for 100-ton scale industrial production in steel companies.
It is mainly the improvement of forging process, which is a very revolutionary study, which greatly improves the performance of steel. The significance to the submarine is very large, because doubling the intensity at the same mass means deeper dives.
It is also very useful for cars. You can replace the existing materials with thinner materials, and the quality of the car will be greatly reduced. This technology relates to the military and economy and belongs to top secret technology.