Question

Hard and soft ferrite composite calculation software

Answer 1

Answer:

Nickel and zinc substituted strontium hexaferrite, SrFe11Zn0.5Ni0.5O19 (SrFe12O19/NiFe2O4/ZnFe2O4) nanoparticles having super paramagnetic nature are synthesized by co-precipitation of chloride salts using 7.5M sodium hydroxide solution. The resulting precursors are heat treated (HT) at 900 and 1200°C for 4h in nitrogen atmosphere. During heat treatment, transformation proceeds as a constant rate of nucleation and three dimensional growth with an activation energy of 176.79kJ/mol. The hysteresis loops show an increase in saturation magnetization from 1.042 to 59.789emu/g with increasing HT temperatures. The ‘as-synthesized’ particles with spherical and needle shapes have size in the range of 20–25nm. Further, these spherical and needle shaped nanoparticles tend to change their morphology to hexagonal plate and pyramidal shapes with increase in HT temperatures. The effect of such a systematic morphological transformation of nanoparticles on dielectric (complex permittivity and permeability) and microwave absorption properties are estimated in X band (8.2–12.2GHz). The maximum reflection loss of the composite reaches −29.62dB (99% power attenuation) at 10.21GHz which suits its application in RADAR absorbing materials.

Answer 2

Nickel and zinc substituted strontium hexaferrite, SrFe11Zn0.5Ni0.5O19 (SrFe12O19/NiFe2O4/ZnFe2O4) nanoparticles having super paramagnetic nature are synthesized by co-precipitation of chloride salts using 7.5M sodium hydroxide solution. The resulting precursors are heat treated (HT) at 900 and 1200°C for n 4h initrogen atmosphere. During heat treatment, transformation proceeds as a constant rate of nucleation and three dimensional growth with an activation energy of 176.79kJ/mol. The hysteresis loops show an increase in saturation magnetization from 1.042 to 59.789emu/g with increasing HT temperatures. The ‘as-synthesized’ particles with spherical and needle shapes have size in the range of 20–25nm. Further, these spherical and needle shaped nanoparticles tend to change their morphology to hexagonal plate and pyramidal shapes with increase in HT temperatures. The effect of such a systematic morphological transformation of nanoparticles on dielectric (complex permittivity and permeability) and microwave absorption properties are estimated in X band (8.2–12.2GHz). The maximum reflection loss of the composite reaches −29.62dB (99% power attenuation) at 10.21GHz which suits its application in RADAR absorbing materials.