Nondestructive evaluation of steels using acoustic and magnetic Barkhausen signals - I. Effect of carbide precipitation and hardness

Journal Article · Wed Jul 01 00:00:00 EDT 1987 · Acta Metall.; (United States)

DOI:https://doi.org/10.1016/0001-6160(87)90096-4· OSTI ID:5524941

Kameda, J; Ranjan, R

The effect of microstructures on acoustic and magnetic Barkhausen signals has been investigated in a quenched and tempered steel and spheroidized steels with various carbon contents. A major peak of the acoustic Barkhausen signal was induced when a magnetic field was increased from zero to the saturation state. A minor peak of the acoustic signal and a single peak of the magnetic signal appeared during the decreasing field. The peak value of the acoustic Barkhausen signal shows a linear dependence on the sweep rate of a magnetic field while that of the magnetic Barkhausen shows a nonlinear one. The increasing tempering temperature which gives rise to a decrease in hardness and an increase in carbide size and spacing caused the acoustic and magnetic Barkhausen peak voltages to increase precipitously and gradually, respectively. In the spheroidized steels, the acoustic peak voltage monotonically decreased with increasing carbon content from 0.17 to 0.96 wt% and the magnetic peak voltage was greatest when the carbon content was 0.46 wt%.

• Research Organization: Ames Lab., Iowa State Univ., Ames, IA 50011
• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 5524941
• Journal Information: Acta Metall.; (United States), Vol. 35:7
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
STEELS
ACOUSTIC TESTING
MAGNETIC TESTING
MICROSTRUCTURE
CARBIDES
CHEMICAL COMPOSITION
HARDNESS
PRECIPITATION
QUENCHING
STRUCTURAL CHEMICAL ANALYSIS
TEMPERING
ALLOYS
CARBON COMPOUNDS
CRYSTAL STRUCTURE
HEAT TREATMENTS
IRON ALLOYS
IRON BASE ALLOYS
MATERIALS TESTING
MECHANICAL PROPERTIES
NONDESTRUCTIVE TESTING
SEPARATION PROCESSES
TESTING
360102* - Metals & Alloys- Structure & Phase Studies