Design and Fabrication of IC Based Magnetic Hysteresis Loop Tracer Sensitive to Low Fields

Mahendra. M. Khandpekar1, Amit T. Singh2

1Department of Physics, B. K. Birla College (Empowered Autonomous Status), Affl: University of Mumbai, Kalyan – 421301, Maharashtra, India, Email: dr_mmk1968@yahoo.com

2Department of Physics, K. M. Agrawal Jr. College, Kalyan- 421 304, Maharashtra, India.

1.0   Abstract:In paper the design and fabrication of an IC OP-07 based magnetic hysteresis loop tracer for low magnetic field up to 10 Oe. The high loop gain of IC OP-07 is able to amplify even the minute changes in the magnetic flux which is needed for accurate working of a B-H loop tracer. The circuit is found to be sensitive to feeble signals. Compared to the conventional B-H loop tracer a separate phase shifter has been used along X-channel providing more circuit flexibility. The designed instrument has been used to measure the apparent coercivity, apparent retentivity and saturation magnetization using minor loops for Ferromagnetic (Fe) and Ferrimagnetic (Mn-Zn) samples. The instrument works at a frequency of 50Hz and the cylindrical samples with a diameter to length ratio of 10 which is seen to minimize the demagnetizing field factor. Hysteresis loss is found to decrease with the decrease in the current of the solenoid. Lowering of magnetic field shows the formation of Rayleigh’s loop.

2.0   Key words: Magnetic, Hysteresis, Integrated Circuit, Loop Tracer, Low field