Holmium Metal - Material Information

Holmium is a rare-earth metal from the lanthanide series, recognized for its outstanding magnetic properties and remarkable neutron absorption capacity. Discovered independently by P.T. Cleve and J.-L. Soret in 1878, holmium is soft, malleable, and silvery in appearance. Although it slowly oxidizes in air, it remains highly stable under controlled conditions, making it an essential element in magnetic, optical, and nuclear technologies.

Material Overview

Holmium crystallizes in a hexagonal close-packed (hcp) structure with a density of 8.80 g·cm?³ and a melting point of 1474 °C. It exhibits complex magnetic behavior, transitioning from paramagnetic above 133 K to antiferromagnetic between 20–133 K and ferromagnetic below 20 K (Rhodes et al., 1958). This strong magnetocrystalline anisotropy makes holmium an exceptional material for magnetic flux concentrators. Zverev et al. (2015) provided a refined magnetic phase diagram for single-crystal holmium, identifying field-dependent magnetothermal transitions along its crystallographic axes up to 100 kOe. Furthermore, Yamamoto et al. (2022) reported that holmium trialuminide (HoAl?) exhibits a complex antiferromagnetic order with magnetocaloric effects around 10–15 K, indicating its potential for low-temperature cooling systems. Di et al. (2018) demonstrated that partial substitution of holmium in Nd–Fe–B systems enhances corrosion resistance and thermal stability due to the formation of stable (Nd,Ho)-O boundary phases.

Applications and Advantages

Holmium’s exceptionally high magnetic moment (10.6 ?_B per atom) makes it ideal for use in magnetic flux concentrators, magnetic refrigeration, and nuclear control rods. Its neutron absorption cross-section (~64 barns) allows it to act as a reactor poison, stabilizing fission chain reactions. Holmium-doped materials are also used in solid-state lasers operating at 2.1 ?m for medical and LIDAR systems. Recent advancements in alloy development have shown that Ho-based intermetallics possess improved mechanical hardness and oxidation stability (Cao et al., 2021), expanding its applications to permanent magnets and electronic shielding materials. Combined with its optical absorption capabilities, holmium remains a critical material in photonics, magnetism, and nuclear science.

Goodfellow Availability

Goodfellow offers Holmium metal in multiple research-grade forms such as foil, wire, and powder. Each product is produced with high purity and controlled surface quality to ensure consistent magnetic and mechanical properties. Custom geometries and high-vacuum processing options are available to meet specific experimental or engineering requirements.

Explore Holmium (Ho) and other advanced materials in Goodfellow’s online catalogue: Goodfellow product finder.

References

• Rhodes, B. L., Legvold, S., & Spedding, F. H. (1958). Magnetic properties of holmium and thulium metals. Physical Review, 109(6), 1547–1552.
• Zverev, V. I., Tishin, A. M., Mudryk, Y., Gschneidner, K. A., & Pecharsky, V. K. (2015). Magnetic and magnetothermal properties of single-crystal holmium. Journal of Physics: Condensed Matter, 27(14), 146002.
• Yamamoto, T., de Castro, P. B., Terashima, K., Saito, A., Takeya, H., & Takano, Y. (2022). Magnetic, thermal, and magnetocaloric properties of HoAl? with polytypic phases. Journal of Magnetism and Magnetic Materials, 563, 169801.
• Di, J., Guo, S., Chen, L., Yi, P., Ding, G., Chen, K., Li, M., Lee, D., & Yan, A. (2018). Improved corrosion resistance and thermal stability of sintered Nd–Fe–B magnets with holmium substitution. Journal of Rare Earths, 36(8), 841–848.
• Cao, Y., Liu, Y., Zhang, P., Xu, G., Liu, J., Chen, J., Yi, X., & Wu, Y. (2021). Corrosion resistance and mechanical properties of (Ho,Nd)FeB magnets. Journal of Rare Earths, 39(11), 1189–1198.