Embedded Transducers in Polymeric Coatings on Metallic Substrates

This paper provides a tutorial introduction to recently devised technologies for transducers embedded within the organic coatings of metallic (or, more generally, of electrically conductive) mechanical components, such as organically coated flat sheet steel, and three-dimensional machine parts, such as bearing supports and mold jaws. The integration of sensors and actuators into the surface coating of these components is of particular interest: first, it allows assessment of physical parameters at locally defined positions that are not accessible with usual discrete transducers; and second, a functionalized component equipped with sensory intelligence adds value for producer and customer. However, realization of embedded transducers entails challenges posed by (i) any potential preexisting protective organic coating and (ii) the shape and surface roughness of the underlying metallic substrate. This tutorial addresses the major issues that arise when sensors or actuators are to be integrated into the organic coating of an electrically conductive machine part, and provides hints and guidelines for successful realization based on recent research.