Study On The Insulation Treatment Of FeSiBP Powder Surface And The Electromagnetic Properties Of Amorphous Soft Magnetic Composite Powder Cores

Fe-based amorphous soft magnetic material has high strength,high hardness,strong corrosion resistance and other mechanical properties,and excellent soft magnetic properties.It uses the green manufacturing technology with the shortest flow of metallurgy,and is called a new generation of"dual green"energy efficient material.The Fe-based amorphous soft magnetic material has a high magnetic induction（Bs）,but its resistivityρis low and generates a large eddy current at a slightly higher frequency,which is suitable for low frequencies.Ferrite soft magnetic materials have high resistivity and are suitable for high frequencies,but their ferrimagnetic properties determine that Bs is only 1/4-1/3 of that of soft magnetic materials,which is not conducive to miniaturization.The insulating coating of the soft magnetic composite material significantly reduces the static and dynamic magnetic properties of the soft magnetic material.Therefore,the research and development of new soft magnetic composites（SMCs）with high saturation magnetic induction,large permeability and low coercive force,high electrical resistivity and low core loss have become hot spots at home and abroad.In this paper,Fe₇₆Si₉B₁₀P₅ amorphous soft magnetic powder particles coated with（NiZn）Fe₂O₄ precursor were prepared by sol-gel process,and then sintered by spark plasma sintering at sintering temperatures of 467°C,487°C,507°C,527°C and under the uniaxial pressure condition of 550 MPa,Fe₇₆Si₉B₁₀P₅/（NiZn）Fe₂O₄ soft magnetic composites were prepared.SEMs,XRD,VSM,and AT512 precision resistance tester were used to test the SMCs prepared by SPS.The analysis found that the Fe-based amorphous powders formed a thin,uniform and tightly bonded spinel structure（NiZn）Fe₂O₄ insulation layer.The thickness is about 400 nm.When the sintering temperature is 467°C,the Fe₇₆Si₉B₁₀P₅/（NiZn）Fe₂O₄ soft magnetic composite has the highest resistivity,which is1306μΩ·cm.When the sintering temperature is 487°C,the saturation magnetization Ms of the SMCs is 1.46 T.The magnetic permeability is 370 at a frequency of 10 kHz.The density of the samples is high,and the density is more than 98%.When the sintering temperature is 527°C,the microhardness value of the samples of SMCs is 1218 HV.In this paper,a sol-gel soft ferrite insulation coating design of Fe-based amorphous soft magnetic composites is used to construct an SMCs insulation design method and related theory based on spark plasma sintering technology to solve the problem of reducing magnetic permeability due to the insulation layer.Problems,while effectively suppressing eddy current losses.It provides a possibility for the research and development of high-performance novel amorphous soft magnetic composites.