The detection of underwater objects is one of the most critical technologies, and there have been constant efforts for developing sophisticated sonar systems in naval warfare. Against such efforts, the countermeasure of hiding underwater vehicles, equipment and weapons is another technological challenge. One of the effective countermeasures against sonic detection for the submarines and other underwater objects, such as naval mines, is to employ composite/hybrid materials to prevent ease of detection. Geometrical forms, shapes and layers, along with the tuning of the acoustical impedance, lead to a considerable decrease of the sonar signals via absorption of the sonic waves. In this study, an original and novel design of multi-layered composite/hybrid structure was developed and underwater acoustic testing procedures of reflection, transmission and scattering were applied in 80 kHz100 kHz frequency range. The findings obtained in this study showed that the multi-layered composite/hybrid materials with porous structure possess much lower values in millivolt than steel plates and might be potential candidates as covering and/or casing materials for underwater mines to reduce the acoustical signature against detection and identification.

One of the major tasks of the underwater warfare is to detect underwater objects such as vehicles, vessels, weapons and equipment. The conduct of underwater warfare mostly depends upon the advancement of detection and identification sensors and materials. The wide variation in types and characteristics of materials may affect the underwater detection capabilities despite recently developed sonar systems. The materials with high porosity are known to provide lower acoustical signature than conventional metallic plates in common. The aim of this study is to examine the acoustical signature and the efficiency of open celled SiC foam ceramics as covering and/or casing material for naval mines. Sonar frequencies widely used in mine countermeasure operations for detection purposes, 80kHz, 85kHz, 90khZ, 95kHz and 100kHz were applied to the acoustic tests. The experimental results obtained from the study shows that the SiC foam ceramic plate leads a 19,2% reduction in reflection, 90,5 % and 96 % lower values are obtained in transmission and 78,4 % and 68,6 % lower values are obtained at 60° and 30° in scattering compared to the reference steel plate.

One of the major tasks of the underwater warfare is to detect underwater objects such as vehicles, vessels, weapons and equipment. The conduct of underwater warfare mostly depends upon the advancement of detection and identification sensors and materials. The wide variation in types and characteristics of materials may affect the underwater detection capabilities despite recently developed sonar systems. The materials with high porosity are known to provide lower acoustical signature than conventional metallic plates in common. The aim of this study is to examine the acoustical signature and the efficiency of open celled SiC foam ceramics as covering and/or casing material for naval mines. Sonar frequencies widely used in mine countermeasure operations for detection purposes, 80 kHz, 85 kHz, 90khZ, 95 kHz and 100 kHz were applied to the acoustic tests. The experimental results obtained from the study shows that the SiC foam ceramic plate leads a 19,2% reduction in reflection, 90,5% and 96% lower values are obtained in transmission and 78,4% and 68,6% lower values are obtained at 60° and 30° in scattering compared to the reference steel plate. Article Highlights This study investigates underwater acoustic performance of open celled SiC foam ceramics the range of 80–100 kHz in the acoustic test pool environment for the very first time. Highly tortuose and porous structure of open celled SiC foam ceramic leads a considerable decrease in scattering, reflection and transmission properties. The study reveals that SiC foams ceramics are potential candidates in reducing acoustical signature as covering and/or casing material for future naval mine applications.