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[求助] 线圈骨架注射模设计

The nanocomposite multilayer film was prepared using
sol–gel method. The TiO2and ferrite sols were synthe-
sized respectively first. The TiO2sol was obtained after
adding tetrabutyl titanate, diethanolanine and a little of
watertotheabsolutealcohol,withstirringfortwohours.
According to the composition of BaFe10.5Al1.5O19,
BaFe10.1Al1.9O19 and BaFe11.4Cr0.6O19 respectively,
stoichiometric
amount
of
barium
nitrate,
ferric
nitrate, aluminum nitrate or chromium nitrate were
dissolved in 60?C ethylene glycol with the addition of
citric acid. After the ethylene diamine was added to
adjust the pH value to 7.0, the ferrites precursor
sols were formed. Depending on the weight ratio of
ferrite to titanium dioxide for 3:5, three mixed sols were
prepared. The mixed sol of BaFe10.1Al1.9O19and TiO2
was first spin coated onto a quartz glass plate, which had
beenpreviouslycleanedbydeionizedwaterandalcohol.
The spin speed was 3,000 rpm and the spin time
was 15 s. The composite film was dried at 60 ?C for
30 min. Then the above spin process was repeated
successively with the other two mixed sols containing
BaFe10.5Al1.5O19and BaFe11.4Cr0.6O19. Finally, three
layer composite films were calcined at 850 ?C for one
hour.
Surface morphology of the multilayer film was
analyzed with atomic force microscopy (AFM), which
was performed on the UHV-SPM. The scanning area
was 2 ·2 lm. The crystalline structures of multilayer
film were determined with X-ray diffraction (XRD)
carried out on a Bruker-AXS D8 Advanced diffrac-
tometer with Cu Karadiation in the 2h range from 10?
to 90?, by steps of 0.02?. The microwave absorption
property was expressed in microwave loss efficiency.
The composite film was scraped off the quartz glass
and collected together. The powders were filled into a
30 · 30 · 3 mm
polytetrafluoroethylene
box
and
pressed tightly. The transmission and reflection coef-
ficients were measured with microstrip transmission
line in 8722ES vector network analyzer in the fre-
quency range from 5 GHz to 15 GHz. The microwave
loss
AdBwas calculated according to Eq. 1.
where PTis the transmission wave power; PIis the
incident wave power and PR is the reflection wave
power. The microwave loss of the polytetrafluoroeth-
ylene box was subtracted.
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