Title :
Passive nondestructive evaluation of ferromagnetic materials during deformation using SQUID gradiometers
Author :
Mignogna, R.B. ; Browning, V. ; Gubser, D.U. ; Schechter, R.S. ; Simmonds, K.E. ; Weinstock, H.
Author_Institution :
US Naval Res. Lab., Washington, DC, USA
fDate :
3/1/1993 12:00:00 AM
Abstract :
An experimental system is described for in situ passive measurement of changes in the magnetic field of ferromagnetic materials subject to tensile deformation. Changes in magnetic field during deformation are monitored using a three-axes first-order superconducting quantum interference device (SQUID) gradiometer. The gradiometer is held in a fixed position while a horizontal load frame has been constructed from nonferromagnetic materials. Results are presented for cold-rolled steel specimens. The magnetic field gradient was measured by scanning the specimen in the x-y plane while at a constant stress at a fixed distance from the tail of the SQUID dewar.<>
Keywords :
SQUIDs; carbon steel; ferromagnetic properties of substances; magnetic field measurement; magnetomechanical effects; magnetometers; nondestructive testing; tensile testing; 1018 steel; SQUID dewar; SQUID gradiometers; cold-rolled steel specimens; ferromagnetic materials; first-order superconducting quantum interference device; horizontal load frame; magnetic field; magnetic field gradient; nondestructive evaluation; nonferromagnetic materials; situ passive measurement; tensile deformation; Interference; Magnetic field measurement; Magnetic materials; Monitoring; SQUIDs; Steel; Stress measurement; Superconducting devices; Superconducting materials; Tail;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
