Chinese name: iron boride
Chemical formula: FEB
Molecular weight: 66.66
Melting point: 1652℃
Density: 7.15g/ML (25/4℃)
CAS number :12006-84-7
Production method:
1. Boron and iron are mixed according to the molar ratio of 1∶1, and co-heated in argon at 1200 ~ 1300℃.
2. FeS and BCl3 are reacted in hydrogen at temperatures above 500 ° C, or prepared by the reaction of ferrous chloride solution with sodium borohydride (NaBH4).
Material structure:
Iron boride is arranged in a zigzag chain, with the iron atoms at the corners of the triangular prism and the boron atoms at the center of the triangular prism, linked in a zigzag chain by covalent bonds.
Physical and chemical properties:
The melting point of iron boride is 1652℃, the density is 7.15g/mL, soluble in dilute and concentrated nitric acid, concentrated and 1:1 hydrochloric acid solution, 1:1 H2SO4 and HClO4, μeff=1.1μB. It exists as alpha - at low temperatures and beta - with the same Tc (602K) at high temperatures. The magnetic moment changes from α to β. Both can form ferromagnets. Reacts with boiling water. Hard texture, refractory, good corrosion resistance.
Iron boride has the properties of ceramics, such as high hardness, as well as the properties of metals, such as thermal and electrical conductivity. The boride coating on iron surface has excellent mechanical properties, frictional properties and anti-corrosion properties. Iron monoborate (FeB) is a gray powder that is insoluble in water. FeB is harder than Fe2B, but more brittle and more likely to break on impact.
Purpose:
1. Target material;
2. Iron boron is a strong deoxidizer and boron addition agent in steelmaking production. The biggest role of boron in steel is to significantly improve the hardenability and replace a large number of alloying elements with only a very small amount of boron, and it can also improve mechanical properties, cold deformation properties, welding properties and high temperature properties.
A kind of ultra-fine iron boride prepared:
After mixing ferrous gluconate solution with boric acid solution, spray drying was performed to obtain spray drying material. The molar ratio of ferrous gluconate solution to boric acid was 1:1.01 1.02; The spray drying material was sintered in methane atmosphere, sintering time was 5 10h, sintering temperature was 800 1200℃, the reaction was obtained. The regenerated material was further injected with carbon dioxide and reacted at 700 850℃ for 2 4h to obtain the sinter. Ultrafine iron boride was obtained by pulverizing, screening and vacuum packing the sinter. The method can prepare ultrafine iron boride with small particle size, large BET and high purity.
