bdd6258ba8b23538849329a5390828d3.ppt
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Cryogen Free Desktop Vibrating Sample Magnetometer (VSM) to 5 Tesla
Background • Cryogenic Ltd are pioneers of Cryogen Free magnet systems. • Prior to this development high magnetic fields were only available to those with access to liquid helium. • Alternatives such as water cooled electromagnets require very large power units. • The cryogen free technology allows magnets of a wide range of fields and dimensions to be built using the same method of refrigeration.
5 Tesla Desktop Cryogen Free VSM
Cryogen Free VSM The Basic system includes: • The superconducting magnet up to 5 Tesla • The VSM probe. • Cryocooler and compressor. • Electronics Rack housing the bipolar magnet power supply, temperature controller, thermometers, scanner and the measurement option electronics. • The computer (Pentium based with high resolution TFT screen), including all software, I/O, IEEE and other necessary cards for measurements. • Lab. VIEW operating software.
Desktop Cryogen Free VSM Magnetic field range: up to 5 Tesla Central field homogeneity: 0. 1% over samples (0. 01% optional) Persistent mode decay rate: 10 ppm / hour (optional switch) Field Sweep rate: 0. 5 T/min Sample temperature range: 1) Room temperature only 2) 77 K to 300 K 3) up to 1000 K with furnace Maximum sample size (in VSM): 8 mm diameter VSM vibration amplitude: 0. 5, 1, 2 mm peak to peak (optically controlled) VSM vibration frequency: 15 to 25 Hz Typical Base noise (with 10 second averaging): 10 -6 emu Accuracy and reproducibility: 0. 5% Temperature setting period (if applicable): 5 minutes if d. T is ~5 K Temperature control (if applicable): (with Lakeshore series unit) 100 m. K @ 100 K
Desktop Cryogen Free VSM Model Range Model No mini-CFM-3 T-51 -H 3 mini-CFM-5 T-51 -H 3 2 Tesla Solenoid 3 Tesla Solenoid 5 Tesla solenoid Field direction to bore Axial Homogeneity in 10 mm DSV 0. 1% Persistency (optional switch) 1 x 10 -5 per hour 51 mm bore Cooldown 300 K to operating temperature 14 hours 15 hours 18 hours Ramp time 0 Tesla to full field 5 minutes 6 minutes 10 minutes Operating current <60 Amps Magnetic field Room temperature bore
The Advantages of Cryogen Free Facility • Low Operating Costs as liquid helium is not required. • Ease of use as there are no cryogen transfers to make. • Independent and convenient operation • Fast Ramping capability • Automated operation • May be used in any orientation.
Automation The system is installed with the National Instruments Lab. VIEW operating software and a standard Cryogenic applications package, which allows the complete system to be run under computer control. This allows: • Control of magnetic field • Fail-safe shutdown even with power failure. • Better data presentation, real data and then curve fitted data. • Full development software licence allowing the user to develop special applications
Optional Extras Option 2: High temperature oven insert To perform measurements at above room temperature, an oven insert is offered which increases the standard temperature range. In normal operation, the system has a continuous temperature range of 77 K to 300 K. With the oven insert this can complemented by a temperature range of 300 K to 1000 K.
Other Applications Of Cryogen free magnets. • Magneto-optical effects, EPR, ESR and NMR • Industrial applications eg; process of industrial minerals including China Clay and Calcium Carbonate. • Synchrotron and Gyrotron magnets to generate X-rays and tuneable microwave. • Medical Applications • Magnetic Resonance Imaging
bdd6258ba8b23538849329a5390828d3.ppt