Thermal conductivity of pure iron at various temperatures

<strong>Thermal conductivity of pure iron at various temperatures</strong> Junjie Chen Contributor: Junjie Chen, ORCID: 0000-0001-5055-4309, E-mail address: [e-mail], Department of Energy and Power Engineering, School of Mechanical and Power Engineering, Henan Polytechnic University, 2000 Century Avenue, Jiaozuo, Henan, 454000, P.R. China Iron is a chemical element with the atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in front of oxygen, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust. In its metallic state, iron is rare in the Earth's crust, limited mainly to deposition by meteorites. Iron ores, by contrast, are among the most abundant in the Earth's crust, although extracting usable metal from them requires kilns or furnaces capable of reaching 1,500 degrees Celsius or higher, about 500 degrees Celsius higher than that required to smelt copper. In the modern world, iron alloys, such as steel, stainless steel, cast iron and special steels, are by far the most common industrial metals, because of their mechanical properties and low cost. The iron and steel industry is thus very important economically. Pristine and smooth pure iron surfaces are mirror-like silvery-gray. However, iron reacts readily with oxygen and water to give brown to black hydrated iron oxides, commonly known as rust. Unlike the oxides of some other metals, that form passivating layers, rust occupies more volume than the metal and thus flakes off, exposing fresh surfaces for corrosion. Although iron readily reacts, high purity iron, called electrolytic iron, has better corrosion resistance. Thermodynamic temperature (degrees kelvin), Thermal conductivity (watts per meter-kelvin) 2 149 3 224 4 297 5 371 6 442 7 513 8 580 9 645 10 705 20 997 30 814 40 555 50 372 60 265 70 204 80 168 90 146 100 132 200 94 273.2 83.5 300 80.3 400 69.4 500 61.3 600 54.7 700 48.7 800 43.3 900 38 1000 32.6 1100 29.7 1183 29.9 1183 27.9 1200 28.2 1300 29.9 1400 30.9 1500 31.8