INVESTIGATION OF MAGNETIC HYSTERESIS PROPERTIES OF ISOTROPIC MAGNETICALLY HARD ALLOYS OF THE Fe-Cr-Co SYSTEM ALLOYED WITH TUNGSTEN

Abstract

Hard magnetic alloys Fe-30Cr-20Co (wt.%) alloyed with tungsten in an amount of up to 3 wt.% were obtained by powder metallurgy. A study of magnetic properties showed that tungsten additions increase the values of the coercivity Hc and the maximum energy product (BH)max, but at the same time reduce the residual induction Br. This effect increases with increasing tungsten content in the material. The maximum values of Hc (55.8 kA/m) and (BH)max (17.2 kJ/m3) are observed in the alloy alloyed with 3 wt.% W. At the same time, the alloys studied in the work turned out to be sensitive to thermal conditions processing. According to X-ray phase analysis, after a full processing cycle, alloys contain a noticeable proportion of non-magnetic ɣ-phase, but the magnetic properties correspond to the level of cast analogues. During compression tests, all samples of tungsten alloyed alloys failed before reaching a deformation rate of 20%, while the unalloyed Fe-30Cr-20Co (wt.%) alloy deformed without failure under these conditions. Thus, tungsten additives reduce the ductility of the material.