Influence of Laser Power on Achieving Ultra Low Stiffness in Resistive Strain Gauges Through on Laser Bonding Transfer-Patterning of Multiwall Carbon Nanotubes (MWCNTs) onto Polydimethylsiloxane (PDMS) Film

This study describes a novel stretchable and very sensitive strain gauge enabled by laser-joining carbon nanotubes, resulting in unique architectures forming macroscopic web networks. The stiffness of the resistive strain sensor created by laser material patterning is reduced significantly, from 1.5824 to 0.142 kN m⁻¹, corresponding to a change in laser power from 0 to 0.436 W. Many benefits of laser-based bonding include precise and flexible local pattern production with minimal energy impact on the flexible substrate. Furthermore, the maximum Gauge factor of the sensor exhibits diverse trends with different strains, generating values of GF = 12.8 for strains less than 2.5% and GF = 165 for strains greater than 2.5% during extension-retraction cycles. These disparities are the result of a dynamic fight between network degradation and regeneration.