Test Cryostat at Variable Temperature and High Magnetic Field Saclay (CETACES)

Context

Test station created in 2003 for the characterization of superconducting strands to meet R&D needs of large-scale projects (support in the strand choice in the early stages).

Critical current measurements on superconducting strands (1.8 K ≤ T ≤ 60 K) under high magnetic field (B ≤ 17 T).

So far, there has been no need to work with higher temperature.

Nevertheless, the station could operate at T = 200 K, with however lower performances in terms of temperature stability and capacity of the current leads.

Technical means

Stabilized power supply, I < 3000 A,
Temperature control of the sample, with a 1000 m³ /h pumping group Roots,
Sample holder [1.8 K, 4.2 K] equipped with a JT valve,
Evaporator cryostat (P =10 W),
Field, temperature and current control by computer.

Two cryostats with associated equipment:

CETACES 1

- Generation of a magnetic field B ≤ 17 T, with a hybrid solenoid (Nb3Sn / NbTi) contained in the cryostat,

- Sample temperature 1.8 K ≤ T ≤ 200 K,

- Useful diameter of the warm bore: Φ = 49 mm (Vamas sample),

- 2 sample holders with concentric current leads (one sample holder suitable for the temperature range [1.8 K, 4.2 K], and the other one used in gas version, over the range [4.2 K, 60 K]),

- Maximum current in the sample: 2000 A for 1.8 K ≤ T ≤ 4.2 K,

1000 A for 4.2 K ≤ T ≤ 60 K,

- Thermo-regulated sample:

± 0.05 K in the range 1.8 K ≤ T ≤ 60 K,

± 0.5 K in the range 60 K ≤ T ≤ 200 K.

CETACES 2

- Generation of a magnetic field B ≤ 13 T,

- Identical helium bath for the magnet and the sample,

- The sample temperature can take only certain specific values depending on the value of the generated magnetic field:

More precisely: - for 0 T ≤ B ≤ 11 T, T = 4.2 K,

- for 11 T ≤ B ≤ 13 T, T = 1.8 K.

- Useful diameter: Φ = 93 mm,

- Maximum current in the sample : I = 2000 A.

Achievements, related projects

Critical current measurements on superconducting strands in the framework of the Nb3Sn, R3B, ITER, NED, ISEULT projects.

Technical steps, expertise

Adjustment and tuning of measurement and security chains,
Check at high and low temperatures of the quality and insulation of measurements and diagnostics,
Cooling of the magnet (the magnet remains cold on an almost permanent basis, low consumption),
Check-up of the « Magnet Safety System » (MSS),
Securing the area (markup),
Partial operating tests before increasing the current to its nominal value,
Calibration of the station with a superconducting CERN strand whose characteristics are known (error <5%),
Critical current measurements on the sample to be tested.

Contact:

#3987 - Last update : 07/21 2017

Division of accelerators, cryogenics and magnetism

Institute of research into the fundamental laws of the Universe