Ferrites are widely applied in scientific research experiments. One of the promissing fields of application is particle accelerator. The scientists keep on trying to understand the Universe by hiting atoms with titanic strength. For particles accelerating in the chamber the special large magnetic toroids are required.
Especially for such applications Ferroxcube technical specialists developed a range of large ferrite toroids.
The toroids of large sizes are successfully applied in very-high-power lasers and radar equipment. In table 1 some possible toroids sizes are listed. However toroids are being manufactured according to sizes coordinated with the customers.
| The toroid code | D, mm | d, mm | h, mm | le, mm | Ae, mm² | Ve, mm³ | Weight, g |
|---|---|---|---|---|---|---|---|
| T170/110/20 | 170 | 110 | 20 | 426 | 591 | 252000 | 1300 |
| T240/160/20 | 240 | 160 | 20 | 611 | 789 | 482000 | 2500 |
| T350/180/25 | 350 | 180 | 25 | 774 | 2050 | 1590000 | ≈ |
| T440/250/25 | 440 | 250 | 25 | 1030 | 2310 | 2380000 | ≈ |
| T500/240/25 | 500 | 240 | 25 | 1060 | 3100 | 3300000 | 19000 |
| T500/300/25 | 500 | 300 | 25 | 1200 | 2450 | 2950000 | 16000 |
Taking into account the dynamic behaviour of a system in a pulse mode toroids are being manufactured on the base of ferrite materials with low losses at high magnetic-flux density.The properties of materials used when producing toroids applied in particle accelerators are listed in table 2.
| Characteristics | Materials | ||||
| 8C11 | 8C12 | 4M2 | 4E2 | 4B3 | |
| μi (±20%) | 1200 | 900 | 140 | 25 |
300 |
| μrem approximately | 850 | 600 | 130 | 20 | - |
| Bs 25°C (mT, 800 А/m) | ≥300 | 280 | 250 | 250 | ≥300 |
| Bs 40°C (mТ, 800 А/m) | ≥280 | 250 | 220 | 220 | - |
| Hc (А/m, after 800 А/m) | ≤20 | 30 | 100 | 500 | <80 |
| ρ DC (Ohm) | >105 | >105 | >105 | >105 | >105 |
| Tc (°C) | ≥125 | ≥125 | ≥150 | ≥400 | ≥250 |
μQat frequency 200 kHz: |
15x103 9x103 4x103 |
||||
| μQ at frequency 500 kHz: 10 mТ 20 mТ 50 mТ |
10x103 6x103 2,5x103 |
||||
| μQ at frequency 1 MHz: 5 mТ 10 mT 20 mТ 30 mТ |
10x103 7,5x103 5x103 - |
20x103 20x103 15x10³ 8x10³ |
|||
| μQ at frequency 2,5 MHz: 5 mТ 10 mТ 20 mТ 30 mТ |
20x103 20x103 15x10³ 7x10³ |
||||
| μQ at frequency 5 MHz: 5 mТ 10 mТ 20 mТ 30 mТ |
15x103 15x103 10x10³ 7x10³ |
||||
| μQ at frequency 10 MHz: 5 mТ 10 mТ |
12x10³ 10x10³ |
||||
| μQ at frequency 80 MHz: 1 mТ |
2,5x10³ |
||||
| μQ at frequency 100 MHz: | 2x10³ |
||||
| μQ (%) reduction measured in 10 μs after DC | 9,5 ±0,25 | 4,75 ±0,15 | 19,05 ±0,7 | 100 | 145 |
| differential permeability μΔ after field imposition: 0 А/m 250 А/m 500 А/m 1000 А/m 2000 А/m 3000 А/m |
600 120 50 22 8 5,5 |
130 80 40 22 12 8 |
|||
| Frequency band, MHz | до 2 | 2-10 | 20-100 | ||
| Field of application, distinctive features | magnets for fast beam extraction; high resistance | high frequencies at magnet field imposition | fast recovery after magnet field imposition | high-frequency material | high value of saturation induction |
The structure of the ordering code
T500/300/25-4M2
T — core configuration
500/300/25 — core sizes (inside and outside diameters, height)
4M2 — core material
