Subzero temperature material
Austenitic stainless steel (generally 7-25% nickel) exhibits excellent toughness at very low temperatures. Toughness refers to the ability of a material to absorb energy without being destroyed, which is indispensable in many engineering applications. Structural steel has good toughness at room temperature, but with the decrease of temperature, the ferrite structure will gradually become brittle, so that the steel is not suitable to be used at very low temperature. In contrast, the common nickel-containing austenitic stainless steel can maintain good toughness even at the temperature of liquid helium.
Another series of materials that show good low temperature properties is nickel alloy steel. The necessary toughness and strength can be obtained at the temperature from-60 ℃ to-200 ℃ by adding 1.50 Mel 9.00% nickel to the steel matrix and after proper heat treatment. But if there is no chromium in the mixture, then these steels will not have the inherent corrosion resistance as stainless steel.
Arctic use
It is difficult to recruit people, weld metal and transport goods to and from the Arctic. The key factor of the steel used in the Arctic is the temperature, and the temperature below-50 ℃ is no exception, and it is lower than the ductile-brittle transition temperature of most carbon-manganese structural steels used in the construction of Arctic oil fields.
Other factors that determine the choice of materials used in the Arctic in the oil and gas industry include corrosion resistance and weldability. The former factor is not as important as corrosive oil and gas exploitation and transportation in structural application. The weld must maintain the high fracture toughness of the base metal used in the North Pole. If the toughness of the weld is low, fracture will occur regardless of the quality of the base metal.
Another example comes from the scientific research infrastructure in Antarctica. A Belgian scientific research station was built here in 2008. The facade is made of 1.50mm 304L (UNS S30403) stainless steel plate. This material was chosen because austenitic stainless steel (304L) still shows sufficient strength and toughness at temperatures much lower than-60 ℃.
Click to subscribe to SMM China Nickel Industry chain Annual report to master comprehensive and in-depth industry chain data, research information and SMM professional analysis
