volume | PIER Journals

Abstract

This project proposal addresses the critical need for precise measurement of thin dielectric coatings, which are essential in industries such as aviation, aerospace, and automotive for enhancing structural integrity and protecting against environmental factors. Manual application of these coatings often results in uneven thickness, necessitating a streamlined measurement method. Leveraging advancements in microwave technology, particularly the use of complementary split ring resonators (CSRR), this project introduces a novel measurement approach for coatings on Carbon Fiber Reinforced Polymer (CFRP) composites. By employing electric field coupling of a leaky wave antenna between a cylindrical dielectricloaded sensor and the coatings on CFRP through a double circular ring slot, the method identifies a correlation between resonance frequency and coating thickness. The cavity is integrated with a Vector Network Analyzer (VNA) to detect S₁₁ peaks at the resonance frequency, enabling precise measurement. Initial design comparisons using CST software resulted in a sensor antenna with optimal impedance matching and sensitivity, which was subsequently fabricated and tested in a microwave lab. Remaining objectives include developing a 4th-order regression model to predict coating thickness ranging from 0 to 2 mm for Polyethylene Terephthalate (PET) on CFRP composites and validating the method for industrial applications in aero-engine parts, gas turbines, and automotive structures. Future enhancements will focus on refining the technique for very thin coatings and exploring drone-based inspection methods for comprehensive aircraft analysis. This innovative approach promises a reliable solution for measuring coating thickness, which is crucial for maintaining the performance and safety of advanced composite materials.

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Dr. Arunachalam Ambika

Dr. Chandrapragasam Tharini

Dr. Paransree Chakraborty

Dr. Fateh Lal Lohar

Mr. S. Sadhish Prabhu

Dr. Kanakam Kumaran Arjun

Dr. Kader Meera John Mohamed Muzzammil