Comparative analysis of elastic wave propagation in functionally graded advanced materials with mass loading and size-dependent micropolar substrates

Understanding the propagation behavior of Love waves is crucial for designing acoustic wave sensors with enhanced sensitivity for various sensing applications. This study focuses on improving the performance of Love-type-based devices by enhancing the mass loading sensitivity by investigating wave propagation in advanced layered structures. Two primary configurations are considered: (a) a functionally graded conductive polymer (FGCP)–micropolar layer over a substrate, and (b) a functionally graded piezoelectric fiber-reinforced composite (FGPFRC)–micropolar layer over a substrate. Each configuration is analyzed under two scenarios: model (i) with an air medium, model (ii) with a coated thin mass loading film for the FGCP structure, and model (iii) with an air medium, model (iv) with a coated thin mass loading film for the FGPFRC structure. The velocity equations have been derived by implementing appropriate boundary conditions under both electrically open and short-circuit conditions. The effect of the functionally graded (FG) parameter, layer thickness, micropolar substrate characteristics, PFRC volume fraction, and mass loading sensitivity on the dimensionless phase velocity is examined and illustrated graphically. The results provide insights into optimizing Love-type wave sensor configurations for improved performance in practical applications.