The effects of alloying elements​ on stainless steel The different alloying elements have specific effects on the properties of a stainless steel. It is the combined effect of all the alloying elements, heat treatment, and, to some extent, impurities that determine the property profile of a certain steel grade. It should be noted that the effect of the alloying elements differs to some extent between the different types of stainless steel. Chromium (Cr) This is the most important alloying element and it gives stainless steels their basic corrosion resistance. All stainless steels have a Cr content of at least 10.5% and the corrosion resistance increases the higher chromium content. Chromium also increases the resistance to oxidation at high temperatures and promotes a ferritic microstructure. Nickel (Ni) The main reason for adding nickel is to promote an austenitic microstructure. Nickel generally increases ductility and toughness. It also reduces the corrosion rate in the active state and is therefore advantageous in acidic environments. In precipitation hardening steels nickel is also used to form the intermetallic compounds that are used to increase strength. In martensitic grades adding nickel, combined with reducing carbon content, improves weldability. Molybdenum (Mo) Molybdenum significantly increases the resistance to both uniform and localized corrosion. It slightly increases mechanical strength and strongly promotes a ferritic microstructure. However, molybdenum also enhances the risk for the formation of secondary phases in ferritic, duplex, and austenitic steels. In martensitic steels it increases the hardness at higher tempering temperatures due to its effect on carbide precipitation. Copper (Cu) Copper enhances corrosion resistance to certain acids and promotes an austenitic microstructure. It can also be added to decrease work hardening in grades designed for improved machinability. It may also be added to improve formability. Manganese (Mn) Manganese is generally used to improve hot ductility. Its effect on the ferrite/austenite balance varies with temperature: at low temperature manganese is an austenite stabilizer, but at high temperatures it will stabilize ferrite. Manganese increases the solubility of nitrogen and is used to obtain high nitrogen contents in duplex and austenitic stainless steels. Manganese, as an austenite former, can also replace some of the nickel in stainless steel. Silicon (Si) Silicon increases resistance to oxidation, both at high temperatures and in strongly oxidizing solutions at lower temperatures. It promotes a ferritic microstructure and increases strength. Carbon (C) Carbon is a strong austenite former that also significantly increases mechanical strength. […]

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China urges US to correct unfair anti-dumping duties on steel products BEIJING — China urged the United States to correct its unfair decision to impose high anti-dumping and countervailing duties on imports of Chinese stainless steel sheet and strip, according to a statement released on Feb 4 by the Ministry of Commerce (MOC). The US Department of Commerce said on Feb 2 that it had determined that imports of Chinese stainless steel sheet and strip should be subject to anti-dumping duties from 63.86 percent to 76.64 percent and anti-subsidy duties from 75.6 percent to 190.71 percent. China is disappointed by a series of decisions by the US related to high anti-dumping and anti-subsidy duties on Chinese steel products and questions its unfair investigation methods, said Wang Hejun, head of the MOC trade remedy and investigation bureau. The United States has violated World Trade Organization rules by neglecting the abundant proof offered by Chinese companies and has treated them unfairly simply because of their state-owned-enterprise status, Wang said. The root cause for current challenges facing the steel sector is the sluggish world economy and shrinking demand, which calls for global cooperation instead of protectionism, according to Wang. The US should abide by WTO rules and correct their unfair practices and China will take the necessary steps to protect due rights of Chinese enterprises, Wang added.