The economic boom in China and India has caused a massive increase in the demand for steel in recent years. Between 2000 and 2005, world steel demand increased by 6%. Since 2000, several Indian[23] and Chinese steel firms have risen to prominence like Tata Steel (which bought Corus Group in 2007), Shanghai Baosteel Group Corporation and Shagang Group. ArcelorMittal is however the world's largest steel producer.
The British Geological Survey reports that in 2005, China was the top producer of steel with about one-third world share followed by Japan, Russia and the USA.
In 2008, steel will be traded as a commodity in the London Metal Exchange.
Recycling
Steel is the most widely recycled material in the United States.[24] The steel industry has been actively recycling for more than 150 years, in large part because it is economically advantageous to do so. It is cheaper to recycle steel than to mine iron ore and manipulate it through the production process to form 'new' steel. Steel does not lose any of its inherent physical properties during the recycling process, and has drastically reduced energy and material requirements compared with refinement from iron ore. The energy saved by recycling reduces the annual energy consumption of the industry by about 75%, which is enough to power eighteen million homes for one year.[25] Recycling one ton of steel saves 1,100 kilograms of iron ore, 630 kilograms of coal, and 55 kilograms of limestone.[26] 76 million tons of steel were recycled in 2005.
A pile of steel scrap in Brussels, waiting to be recycled.
In recent years, about three quarters of the steel produced annually has been recycled. However, the numbers are much higher for certain types of products. For example, in both 2004 and 2005, 97.5% of structural steel beams and plates were recycled.[27] Other steel construction elements such as reinforcement bars are recycled at a rate of about 65%. Indeed, structural steel typically contains around 95% recycled steel content, whereas lighter gauge, flat rolled steel contains about 30% reused material.
Because steel beams are manufactured to standardized dimensions, there is often very little waste produced during construction, and any waste that is produced may be recycled. For a typical 2,000-square-foot (200 m2) two-story house, a steel frame is equivalent to about six recycled cars, while a comparable wooden frame house may require as many as 40–50 trees.[25]
Global demand for steel continues to grow, and though there are large amounts of steel existing, much of it is actively in use. As such, recycled steel must be augmented by some first-use metal, derived from raw materials. Commonly recycled steel products include cans, automobiles, appliances, and debris from demolished buildings. A typical appliance is about 65% steel by weight and automobiles are about 66% steel and iron.
While some recycling takes place through the integrated steel mills and the basic oxygen process, most of the recycled steel is melted electrically, either using an electric arc furnace (for production of low-carbon steel) or an induction furnace (for production of some highly-alloyed ferrous products).
Contemporary steel
Modern steels are made with varying combinations of alloy metals to fulfill many purposes.[8] Carbon steel, composed simply of iron and carbon, accounts for 90% of steel production.[1] High strength low alloy steel has small additions (usually <>environmental solvent inks
Electronic Subassembly Modules
Electrical Insulating Components
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