Special type steel also makes alloy steel, it is a kind of rolled steel. Special type steel is right amount in carbon steel ground join a kind or a few kinds of alloying element, make the constituent structure of steel produces change, make steel has all sorts of different special property thereby. After the Second World War, powerful nation of world each military affairs expands demand for what contented ship vessel equips, development developed series high strength naval vessel is marine steel, this is the inchoate rudiment of special type steel. the common steel with photograph common comparing, special type steel is in intensity, stiffness, tenacity, plasticity, anti-corrosive etc performance side is more better than common steel. Workshop of special type steel, mechanical automation had replaced a large number of artificial operation. The FAST astronomy of Guizhou hopes glasses is built with respect to steel of many use special type. The function of special type steel and utility: 1. Wolfram steel, manganese steel: Hardness is very big, production metal machines pedrail of tool, tractor and axle to wait. 2. Manganese silicon steel: Tenacity is particularly strong, make play circle of reed, bedspring to wait. 3. molybdenum steel: Particularly the bent axle that fights high temperature to make an aircraft, strong tool. 4. Tungsten chromium steel: Hardness is big, tenacity does machine tool cutting tool and mould very by force to wait. 5. Nickel chromium steel (stainless steel) : Corrosion resistance can be strong, not easy oxidation makes chemical industry produce the acid-proof tower that go up, medical apparatus and instruments and every day object to wait. Special although steel is subject at steely industry, but part is complex demand of engineering technology of changeful, preparation is high, decided special the diversity of steel product, because composition differs with what craft asks and different breed caused the vast difference on function, distinguish; somewhat on product application domain then meanwhile, the cent of the on any account that produced craft to bring the respect such as capital, technology to enter a doorsill again. The graph controls tapping flow with computer for steely skilled worker. In common iron and steel the big environment of depression of course of study falls, special type iron and steel becomes technology of new generation manufacturing industry to develop the innovatory industry of degree, also be the industry that each country competes. Have about on the world special steel is close norms of about 50000 2000 brands, breed, the world is main special steel production country basically has Sweden, Japan, United States, Germany, France, Italy, Spain, Korea to wait, they hold the whole world 90% above are special steel trade portion. Sweden is the world on special steel is occupied than top nation, specialization with height production is celebrated, japanese spy steel represents world top level, proportion of product high end is large, integrated competition ability is strong. Of our country special steel industry is built for form a complete set of national defence war industry, aerospace at first. Will nearly ten years develop transition to high-grade equipment as the strength of auto industry, mechanical industry, special steel output grows quickly, breed is all ready with each passing day also with diversification. At present output of steel of our country spy occupies world scale to be 15-20% about, special self-sufficient respect got the product research and development of steel, own innovation and high end better progress. Although industry of Chinese spy steel develops faster, but with world developed country photograph comparing returns existence industry intensive to change, dimensions changes rate insufficient; Specialization efficient change insufficient; Special the deep treatment of steel product and outspread and insufficient wait for a problem. The development impetus that because this China is special,steel industry wants to obtain health to last should raise industry of Chinese special steel be spent centrally, wash out backward productivity, accelerate special the technology of steel industry innovates pace. Industries of 32 domestic spy steel produced special steel in all 2007 70.86 million tons, occupy in those days 14.5% of crop of countrywide crude steel.