The effects of milling time and heat treatment on the micro-structural and magnetic behavior of Fe42Ni28Zr8Ta2B10C10 synthesized by mechanical alloying

In this work, the effect of microstructural evolution during milling and its effects on the magnetic behavior of mechanically alloyed Fe42Ni28Zr8Ta2B10C10 were studied by means of X-ray diffraction, transmission electron microscopy, scanning electron microscopy, diffraction scanning calorimetry (DSC), and vibrating sample magnetometer. Results showed that as the milling time increased, the percentage of the amorphous content increased up to 92% at 176 h of milling and then decreased to a level of 85% by further milling to 198 h. The decrease in the amorphous phase was suggested to be the partial recrystallization of the amorphous phase and DSC confirmed this, in the form of a decrease in the internal stress level after a decrease in the amorphous phase. Magnetic results indicated that by increasing the milling time, both magnetic coercivity and saturation magnetization were increased, they then decreased and again increased at a low rate, and finally, at the onset of the partial recrystallization of the amorphous phase, increased rapidly. The results also revealed that the heat treated powders at 500 °C showed the lowest magnetic coercivity of about 11 Oe, which was unique and made them suitable for soft magnetic applications, while heating at a temperature of 650 °C did not improve the magnetic behavior of the powders. - Highlights: ► Amorphous phase content was about 92% at 176 h of milling. ► Coercivity reduced to about 23 Oe at 176 h of milling. ► At 198 h of milling magnetization increased rapidly due to recrystallization. ► Heat treatment reduced the coercivity to about half. ► The obtained coercivity was the lowest among similar alloys