DETERMINATION OF THE PERCENTAGE CONTENT OF FERROMAGNETIC PHASES IN MODEL SAMPLES OF DEPOSITED AUSTENITIC STEEL ER347 BY MAGNETIC PROPERTIES

A specimen simulating the weld structure was fabricated from ER347 AWS A5.9 austenitic welding wire using automatic submerged arc welding to study its phase composition. Magnetic hysteresis loop parameters and the temperature dependences of the specimen’s magnetic susceptibility in an alternating magnetic field were measured. In addition to paramagnetic austenite, the presence of two ferromagnetic phases (phase “1” and phase “2”) were revealed with a total volume content of 5.2%. To determine the percentage content of each ferromagnetic phase, their contributions to the total magnetic susceptibility were separated. The contribution of phase “2” was shown to decrease from 27.5 to 18.7% during heating of the specimen from 50 to 470◦C as the temperature approached the paramagnetic transition region. It was found that after stabilizing annealing, only one ferromagnetic phase remains in the sample, with its content being 3.6%. The study suggests that phase “1” is ferrite, and phase “2” is deformation-induced martensite.