The role of C content on the glass-forming ability and magnetic properties of FeSiBPC amorphous alloys

The new type of Fe_83 − xSi_2.5B₁₂P_2.5C_x (x = 0, 0.5, 1.0, 1.5, 2.0 at%) amorphous soft magnetic system with low cost, high saturation magnetization and low coercivity were designed and prepared by means of rapid quenching. The effect of C on the amorphous formability, thermal stability, and soft magnetic properties in the alloy system were studied. Results suggest that the addition of small atom C can promote the formation of densely atomic structure of alloy, thereby promoted the enhancement of amorphous formability. With the increase of C content, the temperature interval between two crystallization peaks increases first and then decreases. When C content is 1.0 at%, ΔT (T_x2-T_x1) reaches the maximum value, of about 109.9 ℃, which is beneficial to enhance the thermal stability and soft magnetic properties. As the concentration of C is raised, the B_s exhibit a pattern of increases followed by a subsequent decrease, while coercivity changes in the opposite way. When the C content is 1.0 at%, the B_s of the alloy reaches the highest value of 1.78 T and the coercivity exhibits the best which is 14.055 A/m. The results offer important contributions to the design and advancement of high B_s amorphous soft magnetic materials for industrial applications involving amorphous electric motors.