Measurements of magnetic permeability and H{sub c} of magnet steels using digital techniques

Conference · Sun Nov 01 00:00:00 EST 1992

OSTI ID:10104085

Thomas, R; Morgan, G

The magnet-to-magnet variations in the dipole field of superconducting accelerator magnets must fall within specified tolerances to avoid excessive beam losses during injection. At injection field levels ({approximately} 0.4 T for RHIC), the variations in the field attributable to the iron arise from variations in the chemical impurities, cold working and heat treatment. These structure-sensitive effects can be characterized by measuring the permeability and coercive force, H{sub c}, of iron samples. A digital permeameter was developed to perform precise measurements of the magnetic properties of ring samples. An arbitrary function generator and two high-precision digital multimeters were connected to a desktop computer using the IEEE-488 bus, and software was written to automatically acquire and analyze the data. Through the use of the arbitrary waveform generator, the effect of varying the period of the B-H loop and the effect of varying the shape of the H waveform were explored. The effects of annealing, bending and flattening, and temperature on H{sub c} and the relative permeability have been investigated for samples of magnet steel from several manufacturers.

• Research Organization: Brookhaven National Lab., Upton, NY (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 10104085
• Report Number(s): BNL-47851; CONF-9205272-1; ON: DE93002328
• Resource Relation: Conference: 11. annual conference on properties and applications of magnetic materials,Chicago, IL (United States),12-14 May 1992; Other Information: PBD: [1992]
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
36 MATERIALS SCIENCE
SUPERCONDUCTING MAGNETS
MAGNETIC PROPERTIES
MAGNETIC FIELDS
MEASURING METHODS
MAGNETIC SUSCEPTIBILITY
MAGNETIC DIPOLES
WAVE FORMS
TEMPERATURE DEPENDENCE
HYSTERESIS
430303
665412
360104
EXPERIMENTAL FACILITIES AND EQUIPMENT
SUPERCONDUCTING DEVICES
PHYSICAL PROPERTIES