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Updated: May 30, 2026
06:45
Negative Additive Manufacturing of Complex Shaped Boron Carbides
Published on: September 18, 2018
On the ferromagnetic structure of the intermetallic borocarbide TbCo(2)B(2)C
M Elmassalami1, R Moreno, R M Saeed
1Instituto de Fisica, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, 21945-970 Rio de Janeiro, Brazil.
Summary
Single-crystal terbium cobalt borocarbide (TbCo2B2C) exhibits unique ferromagnetic properties below 6.3 K. This behavior, distinct from its isomorphs, arises from differing exchange couplings influenced by lattice parameters and Fermi levels.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism
Background:
- Terbium cobalt borocarbide (TbCo2B2C) belongs to the RCo2B2C family of materials.
- Understanding magnetic phase transitions in rare-earth intermetallic compounds is crucial for developing new magnetic technologies.
Purpose of the Study:
- To investigate the magnetic properties and phase transitions of single-crystal TbCo2B2C.
- To compare the magnetic behavior of TbCo2B2C with other isomorphous borocarbides, such as TbNi2B2C.
Main Methods:
- Magnetization measurements
- Specific heat analysis
- Magnetostriction studies
- Neutron diffraction on single crystals
Main Results:
- Paramagnetic properties follow Curie-Weiss behavior down to liquid nitrogen temperatures, attributed to Tb(3+) moments.
- A ferromagnetic (FM) phase transition occurs below Tc = 6.3 K, with the easy axis along the (100) direction.
- A tetragonal-to-orthorhombic distortion of the unit cell accompanies the FM transition.
- TbCo2B2C exhibits a unique FM state, unlike the incommensurate modulated magnetic state in TbNi2B2C.
Conclusions:
- The distinct magnetic behavior of TbCo2B2C is attributed to differences in exchange couplings.
- Variations in lattice parameters and Fermi levels are identified as key factors influencing these exchange couplings.
- The study highlights the sensitivity of magnetic properties in isomorphous borocarbides to subtle structural and electronic differences.
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