Preparation Of Fe-Based Amorphous Alloys Powder By Mechanical Alloying

Soft magnetic amorphous alloys are applied in functional materials extensively. They contained four groups: Fe-based amorphous alloy, Fe-Ni based amorphous alloy, Co-based amorphous alloy and Fe-based amorphous-nanocrystalline alloys. Fe-based amorphous alloy is a sort of good soft-magnetic material with promising application prospect. They have good parameters (such as Bs), high permeability (μ) and low iron loss. In the thesis, Fe-based amorphous system as the research base, add Ni, B and C three kinds of elements to explore the non-metallic elements on glass forming ability and magnetic properties.Mechanical alloying(MA), which is a new technology, has attracted much attention of material researchers recently, because it can synthesize metastable materials such as amorphous phase, nanocrystallines, super-saturated solid solution, etc.The thesis emphasize on manufacturing Fe-based amorphous alloys powder by mechanical alloying. The paper analyzed how the ball to material ratio and the milling time affect mechanical alloying. Whether the prepared powder occurred the process of glass transition was observed by X-ray diffraction.The microstructure and shape of the powder was observed and analyzed by scanning electron microscopy, and it had the typical morphology of amorphous powders. By using differential scanning calorimetry , we could obtain glass transition temperature Tg , crystallization temperature Tx 1 and supercooled liquid regionΔT x, Fe₅₀Ni₃₀B₂₀ amorphous'ΔT x is 83.7 K, indicating that it had a high glass-forming ability. Using C element instead of partial B element in the Fe₅₀Ni₃₀B₂₀ to observe its glass forming ability and thermal stability.Using vibrating sample magnetometer (VSM) to measure the magnetic properties of Fe-Ni-B and Fe-Ni-B-C amorphous alloys to explore the B and C elements on soft-magnetic properties.