LaB6 ceramic is an inorganic compound classified as a boride. This refractory ceramic material boasts a distinctive deep purple appearance and possesses an impressively high melting point of 2210°C. Additionally, it exhibits insolubility in both water and hydrochloric acid. Interestingly, when subjected to ion bombardment, its physical characteristics undergo a change, resulting in a green coloration instead of its typical dark purple hue.
The unique properties of LaB6 crystals make them exceptionally suited for use as stable electron-emitting media with work functions close to 2.70 eV. This low work function leads to the generation of higher electron currents at lower cathode temperatures compared to tungsten, resulting in greater brightness at the beam focus and an extended operational lifespan. In practice, LaB6 cathodes often demonstrate brightness levels ten times higher and a service life fifty times longer than tungsten cathodes. In electron microscopy applications, these advantages translate into the delivery of more precise beam currents focused on smaller sample areas, improved resolution, and reduced frequency of cathode replacement.
LaB6 ceramic finds wide-ranging applications, including:
1. Thermionic emission (cathode)
2. Applied in scanning electron microscopes
3. Utilized in surface analysis equipment
4. Serving as a plasma source for plasma-enhanced coating (PECVD)
5. Utilized in transmission electron microscopes
6. Used in radiotherapy devices
7. Utilization in vacuum electron beam welding machines
8. Implementation in devices for electron beam surface reforming
9. Employed in electron beam lithography devices
LaB6 ceramic Properties:
| Properties | Unit | LaB6 |
| Purity | % | >99.5 |
| Density | g/cm3 | >4.30 |
| Structure | / | Monocrystalline |
| Vickers hardness | HV | 1065 |
| Shore hardness | HS | HS |
| Thermal conductivity | W/mK | 15 |
| Electrical Conductivity | S/m | 1.83*10^6 |
| Flexural strength | MPa | 165 |
