High Homogeneity Magnets
Cryomagnetics has considerable experience in the engineering and manufacturing of high homogeneity magnets. By high homogeneity, we mean superconducting magnets with better than +/- 0.01% (100 ppm) maximum central field variation over a 10mm diameter spherical volume (DSV).
The winding process for the manufacture of high homogeneity magnet designs cannot duplicate the computer-generated magnet design specification. Trim coils (shims) must be added to correct inhomogeneities. Many magnet designs can achieve +/- 0.001% (10 ppm) over a 10mm DSV homogeneity with trim coils wound in series with the main coil. This insures homogeneity specification is maintained throughout the entire field range of the superconducting magnet.
Other applications, such as NMR experimentation, require the superconducting magnet to have 1 ppm or 0.1 ppm homogeneity over a large homogeneous volume. This is accomplished by the addition of separately chargeable superconducting shim coils. First-order shim coils can achieve 1 ppm homogeneity and include the coils X, Y, Z, Z2. Second order shim coils can achieve 0.1 ppm homogeneity and include the coils X2-Y2, XY, ZY, and ZX.
The majority of high-homogeneity superconducting magnets are custom built to your specifications. Contact us with your specifications.
Standard High Homogeneity Solenoids (other configurations available upon request)
| Model | Field (T) | Clear Bore (inches) | Homogeneity (ppm)* | Current (A) | Inductance (H) |
|---|---|---|---|---|---|
| 70-200-10P | 7.0 | 2.00 | +/- 10 | 78 | 7.0 |
| 70-250-001L | 7.0 | 2.50 | +/- 100 | 35 | 15.0 |
| 70-300-001L | 7.0 | 3.00 | +/- 100 | 58 | 18.2 |
| 80-200-10P | 8.0 | 2.00 | +/- 10 | 45 | 19.4 |
| 80-250-001L | 8.0 | 2.50 | +/- 100 | 47 | 36.7 |
| 80-250-10P | 8.0 | 2.50 | +/- 10 | 77 | 11.6 |
| 90-200-10P | 9.0 | 2.00 | +/- 10 | 82 | 10.2 |
| 90-250-10P | 9.0 | 2.50 | +/- 10 | 80 | 17.6 |
| 90-300-10P | 9.0 | 3.00 | +/- 10 | 79 | 27.0 |
*Homogeneity measured over 10mm diameter spherical volume (DSV).