Effect of Thermo-Magnetic Treatment on Magnetic Properties and Microstructure of Fe40.75Cr32.4Co24.6Mo2.0Ti0.25 Alloy

The magnetic properties and microstructure of Fe_40.75Cr_32.4Co_24.6Mo_2.0Ti_2.0 has been studied at various annealing temperatures in the magnetic field strength up to 320 KA/m. The magnetic properties and microstructures of this alloy was also compared with the Fe₄₃Cr_32.4Co_24.6 alloy. The magnetic properties produced by thermo-magnetic annealing process in Fe_40.75Cr_32.4Co_24.6Mo_2.0Ti_0.25 alloy at 650°C were H_c= 72kA/m (905Oe), B_r= 1.03T (10kG) and B_s = 1.3 T (13kG). The results shows that nonmagnetic γ and σ phases influences both structure and magnetic properties in these alloys. Addition of 0.25% Ti and 2.0% Mo to Fe₄₃Cr_32.4Co_24.6 refines the microstructure by suppressing the nonmagnetic γ phase and improves the magnetic properties due to spinodal decomposition of phases in a preferred direction.