Tetrataenite

Source: Wikipedia, the free encyclopedia.
Tetrataenite
Mohs scale hardness
3.5
Lustermetallic
Streakgray
Diaphaneityopaque
Density8.275
Common impuritiesCo, Cu, P
References[2][3][4]

[1]

[2]

Tetrataenite is a native metal alloy composed of chemically-ordered L10-type FeNi, recognized as a mineral in 1980.[5][6] The mineral is named after its tetragonal crystal structure and its relation to the iron-nickel alloy, taenite.[7] It is one of the mineral phases found in meteoric iron.[8][3][9]

Formation

Tetrataenite forms naturally in iron meteorites that contain taenite that are slow-cooled at a rate of a few degrees per million years, which allows for ordering of the Fe and Ni atoms.[10][11] It is found most abundantly in slow-cooled chondrite meteorites,[12] as well as in mesosiderites.[10] At high (as much as 52%) Ni content and temperatures below 320 °C (the order-disorder transition temperature), tetrataenite is broken down from taenite and distorts its face centered cubic crystal structure to form the tetragonal L10 structure.[13][11]

The L10 phase can be synthetically produced by

electron-irradiation of FeNi below 593 K, by hydrogen-reduction of nanometric NiFe2O4,[11] or by crystallization of Fe–Ni alloys in the presence of traces of phosphorus.[14]

In 2015, it was reported that tetrataenite was found in a terrestrial rock – a

Indo-Myanmar ranges of northeast India.[11]

A laboratory protocol for bulk synthesis, announced in 2022

Mixing iron and nickel together in specific quantities, with a phosphorus catalyst, and smelting the mixture, forms tetrataenite in bulk quantities, in seconds.[15][16] This discovery, announced in 2022, raises hopes that some of the technologies which currently require the use of magnetic alloys containing rare earths metals may be achievable using magnets made of tetrataenite as an alternative, which would reduce dependence on toxic, environmentally harmful rare earth mines.[17]

Crystal structure

Tetrataenite has a highly ordered crystal structure,

cubic crystal structure, but does not have magnetic anisotropy in this form. Three variants of the L10 tetragonal crystal structure have been found, as chemical ordering can occur along any of the three axes.[5]

Magnetic properties

Tetrataenite displays

permanent magnetization, in particular, high coercivity.[6] It has a large uniaxial magnetocrystalline anisotropy[18] and theoretical magnetic energy product, the maximum amount of magnetic energy stored, over 335 kJ m−3.[6]

Applications

Tetrataenite is a candidate for replacing rare-earth permanent magnets such as samarium and neodymium since both iron and nickel are earth-abundant and inexpensive.[19]

See also

References

  1. S2CID 235729616
    .
  2. ^ "Mineralienatlas – Fossilienatlas". www.mineralienatlas.de. Retrieved 1 April 2023.
  3. ^ a b "Tetrataenite: Mineral information, data and localities". Retrieved 1 April 2023.
  4. ^ "Tetrataenite". webmineral.com.
  5. ^
    S2CID 24710267
    .
  6. ^ .
  7. ^ "Tetrataenite: Tetrataenite mineral information and data". www.mindat.org. Retrieved 2018-03-30.
  8. ^ "Tetrataenite". webmineral.com.
  9. ^ "Handbook of Mineralogy – Tetrataenite" (PDF). Retrieved 1 April 2023.
  10. ^ a b c Clarke, Roy S.; Scott, Edward R. D. (March 6, 1980). "Tetrataenite – ordered FeNi, a new mineral in meteorites" (PDF). American Mineralogist. 65: 624–630.
  11. ^
    S2CID 128688369
    .
  12. ^ Barthelmy, Dave. "Tetrataenite Mineral Data". webmineral.com. Retrieved 2018-04-10.
  13. ^ a b "Taenite." Britannica Academic, Encyclopædia Britannica, 6 Nov. 2009. academic-eb-com.ezproxy.neu.edu/levels/collegiate/article/taenite/342903. Accessed 30 Mar. 2018.
  14. S2CID 253108234
    .
  15. .
  16. ^ "Method of tetratenite production and system therefor".
  17. ^ Paddy Hirsch (8 November 2022). "They made a material that doesn't exist on Earth. That's only the start of the story". NPR. Retrieved 1 April 2023.
  18. ISSN 0021-8979
    .
  19. .