Radar Absorbing Materials

Abstract

In this study, elastomer-based radar absorber materials (H-RGCs) prepared using nano-sized conductive fillers present a comparative experimental methodology to characterize the cross-sectional radar field (RSA) reduction efficiency and performance in the 6-17 GHz band with 3°steps from 0 to 360º. The reference material (M-REM) used in the comparison is designed to reduce the radar cross-section area of military land vehicles (tank, truck, ship, etc.) and is currently commercially available. A six-layer, symmetrical and thin radar absorber material with reflective surfaces in both directions, exhibiting excellent broadband properties, was designed and manufactured. Carbon black and graphene nanoplatelets were used to produce the required rubber composite to form the reflective surface and hybrid layer. Similar results were obtained in the measurements made for both materials, and it was seen that the produced material could be used in systems such as ships and military land vehicles for RSA reduction. The results showed that both material types could achieve a reduction of 20 dBsm. The best RSA values, regardless of frequency, are obtained between 24-72º for M-REM, while for H-RGC, it is in the range of 21-72º. It was observed that the RSA values improved as the frequency bandwidth increased for both materials. In the tests performed at 12 GHz frequency for M-REM, the lowest absorption value was measured at 72°, 42.6743 dBsm, and the lowest absorption value for H-RGC was 42.9219 dBsm. The similarity and match between the measurement results of the H-RGC materials produced as an alternative to the commercially used and proven M-REM showed the validity of our design and gave promising results for future studies.

Keywords

• Radar Absorbing Material
• Radar Cross Section Reduction
• Elastomer
• Conductivity Properties
• Functional Composites

Nanoyapılı iletken dolgulu polimer ile geniş bant çok katmanlı radar soğurucu malzemelerin geliştirilmesi

Öz

Bu çalışma, nano boyutlu iletken dolgu malzemeleri kullanılarak hazırlanan elastomer esaslı radar soğurucu malzemelerin (H-RGC), 0-360º arasında 3°’lik adımlar ile 6-17 GHz frekans bant aralığındaki radar kesit alanı (RSA) azaltma verimliliği ve performansını karakterize etmek için karşılaştırmalı deneysel metodoloji sunmaktafdır. Karşılaştırma kapsamında kullanılan referans malzeme (M-REM) askeri kara araçlarının (tank, kamyon, gemi vb) radar kesit alanını azaltmak için tasarlanmış olup hali hazırda ticari olarak satılmaktadır. Mükemmel geniş bant özellikleri sergileyen, her iki yönde yansıtıcı yüzey içeren altı katmanlı, simetrik ve ince radar soğurucu malzeme tasarlanmış ve üretilmiştir. Karbon siyahı ve grafen nanoplateletler, sırasıyla yansıtıcı yüzey ve hibrit katmanı oluşturmak için gerekli kauçuk kompozit üretmek için kullanıldı. Her iki malzeme için yapılan ölçümlerde benzer sonuçlar elde edilmiş olup üretilen malzemenin gemi, askeri kara araçları gibi sistemlerde RSA azaltımında kullanılabileceğini görülmüştür. Sonuçlar, her iki malzeme tipinin de 20 dBsm değerinde bir azaltım sağlayabildiğini göstermiştir. M-REM için frekanstan bağımsız olarak en iyi RSA değerleri 24-72º ’ler arasında elde edilmişken, H-RGC için 21-72º aralığındadır. Her iki malzeme için frekans bant genişliği artıkça RSA değerlerinin de iyileştiği görülmüştür. M-REM için 12 GHz frekans da yapılan testlerde en düşük soğurma değeri 72° de, 42,6743 dBsm , H-RGC için en düşük soğurma değeri olarak 42,9219 dBsm ölçülmüştür. Ticari olarak kullanılan ve geçerliliğini kanıtlamış M-REM’e alternatif olarak ürettilen H-RGC malzemelerinin ölçüm sonuçları arasındaki benzerlik ve eşleşme, tasarımımızın geçerliliğini gösstermiş ve ileri de yapılacak çalışmalar için umut verici sonuçlar elde edilmiştir.

Anahtar Kelimeler

• Radar Soğurma Malzemesi
• Radar Kesit Alanı Azaltımı
• Elastomer
• İletkenlik Özellikleri
• Foksiyonel Kompozitler

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