Structure and Magnetic Properties of Powder Permalloy Fe-Ni

The aim of this work was to prepare powder samples of FeNi by long-time milling of microcrystalline ribbon Fe₁₉Ni₈₁ (sample A) and that of pure elements Fe and Ni (sample B) in low-energy vibratory mill for 1000 h and to investigate their magnetic properties. We found that the coercivity of sample A and sample B steeply increases up to 140 h of milling time and then slowly increases for sample A and decreases for sample B. The magnetic moment of both samples monotonously decreases during the milling. The sample A is solid solution Fe₁₉Ni₈₁ and its structure is stable during the milling. New phases with different Curie temperatures are found in sample B during the milling.