کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1467399 | 990100 | 2009 | 7 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Preparation and properties of silica filled PTFE flexible laminates for microwave circuit applications Preparation and properties of silica filled PTFE flexible laminates for microwave circuit applications](/preview/png/1467399.png)
Micron and nano size silica fillers are incorporated in the PTFE matrix to prepare flexible composite substrates. A proprietary process comprising of sigma mixing, extrusion, calendering followed by hot pressing (SMECH process) has been employed to obtain nearly isotropic and dimensionally stable filled PTFE substrates. Theoretical modeling has been employed to predict the effective dielectric constant of the composite system and validated the results with experimental data. The distribution of particulate filler in the PTFE matrix has been studied using scanning electron microscopy. The linear coefficient of thermal expansion and ultimate tensile strength of the composite systems with respect to filler loading have been found out. Dielectric properties of the composite substrates at X-band frequency (8.2–12.4 GHz) are measured using waveguide cavity perturbation technique. Moisture absorption of fused silica filled substrates is found out conforming to IPC-TM-650 2.6.2.
Journal: Composites Part A: Applied Science and Manufacturing - Volume 40, Issue 8, August 2009, Pages 1179–1185