摘要
Pyrolytic carbon(PyC) coatings are deposited on the Nextel-440 fiber fabrics by chemical vapor deposition(CVD).The dielectric properties of the Nextel-440 fiber fabrics with PyC coatings(Nextel-440/PyC) are investigated in a temperature range from room temperature to 700℃ in X-band. Compared with the permittivity of the original Nextel-440 received,the complex permittivity of the Nextel-440/PyC(the real part εand the imaginary part ε), is significantly improved: εof the Nextel-440/PyC has a positive temperature coefficient, in contrast, εof the Nextel-440/PyC exhibits a negative temperature coefficient. Moreover, the reflection loss in units of d B is calculated. The results indicate that the microwave absorbing properties of the Nextel-440/PyC coatings is enhanced at 700℃ compared with that at lower temperatures.
Pyrolytic carbon(PyC) coatings are deposited on the Nextel-440 fiber fabrics by chemical vapor deposition(CVD).The dielectric properties of the Nextel-440 fiber fabrics with PyC coatings(Nextel-440/PyC) are investigated in a temperature range from room temperature to 700℃ in X-band. Compared with the permittivity of the original Nextel-440 received,the complex permittivity of the Nextel-440/PyC(the real part εand the imaginary part ε), is significantly improved: εof the Nextel-440/PyC has a positive temperature coefficient, in contrast, εof the Nextel-440/PyC exhibits a negative temperature coefficient. Moreover, the reflection loss in units of d B is calculated. The results indicate that the microwave absorbing properties of the Nextel-440/PyC coatings is enhanced at 700℃ compared with that at lower temperatures.
基金
supported by the National Natural Science Foundation of China(Grant No.51072165)
the Fund of the State Key Laboratory of Solidification Processing in Northwestern Polytechnical University,China(Grant Nos.KP201307 and SKLSP201313)
