Cryotribology: Development of cryotribological theories and application to cryogenic devices

Technical Report · Tue Sep 15 00:00:00 EDT 1992

DOI:https://doi.org/10.2172/6946875· OSTI ID:6946875

Iwasa, Y; Michael, P ^[1]; Rabinowicz, E ^[2]

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1. Massachusetts Inst. of Tech., Cambridge, MA (United States)
2. Massachusetts Inst. of Tech., Cambridge, MA (United States) Massachusetts Inst. of Tech., Cambridge, MA (United States). Francis Bitter National Magnet Lab.

High-performance superconducting solenoids are susceptible to premature quenches, or superconducting to normal state transitions, due to abrupt conductor movements within the winding. Abrupt motions involving 5{approximately}10{mu}m conductor displacements dissipate sufficient energy to trigger a quench. Sliding and mechanical behaviors of materials at cryogenic temperatures have been experimentally examined. After accounting for changes in the sliding materials' low-temperature strength properties, we have found that the adhesion theory of friction and wear remains applicable at cryogenic temperatures. The adhesion friction theory suggests two methods for controlling unsteady sliding motions. The first involves the selection of sliding materials whose friction coefficients increase with increasing sliding speed. A number of material pairs have been examined for positive friction-velocity characteristics. This materials-based approach to frictional stabilization does not seem a viable option at 4.2 K. The second altemative is to preprogram the force conditions within high-risk regions of the winding to regulate the occurrence of unsteady sliding motions. Structural models are proposed to account for unsteady conductor motions on a variety of dimensional scales. The models are used to design a small superconducting solenoid. Performance of this solenoid suggests that force-based motion control is a potentially viable design approach for achieving successful dry-wound magnets.

• Research Organization: Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: FG02-85ER13335
• OSTI ID: 6946875
• Report Number(s): DOE/ER/13335-1; ON: DE93000404
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
SUPERCONDUCTING MAGNETS
TRIBOLOGY
MAGNET COILS
PROGRESS REPORT
QUENCHING
SLIDING FRICTION
SOLENOIDS
TEMPERATURE RANGE 0000-0013 K
TEMPERATURE RANGE 0013-0065 K
TEMPERATURE RANGE 0065-0273 K
DOCUMENT TYPES
ELECTRIC COILS
ELECTRICAL EQUIPMENT
ELECTROMAGNETS
EQUIPMENT
FRICTION
MAGNETS
SUPERCONDUCTING DEVICES
TEMPERATURE RANGE
665412* - Superconducting Devices- (1992-)