Scaling relationship among indentation properties of electromagnetic materials at micro- and nanoscale

Electromagnetic materials have been widely employed in micro-functional devices. Using multi-field nanoindentation technique, we have investigated the local deformation behavior of various electromagnetic materials in the form of bulk materials, foils, and thin films under electric or magnetic field. Based on dimensional analysis and experimental data, a field tunable scaling relationship among hardness, reduced contact elastic modulus, and indentation work has been found. Furthermore, a method to determine the hardness and reduced modulus of electromagnetic materials is proposed, which avoids the error from estimating the indentation contact area. This work is meaningful for the characterization of mechanical properties and design of devices made of electromagnetic materials. (C) 2015 AIP Publishing LLC.