Fig. 4: Electrical properties of liquid metal (LM) pattern printed via aerosol jet printing (AJP).

a SEM images of printed patterns before (left) and after (right) compression using an iron rod (scale bar: 1 μm). The experiment was repeated independently three times with similar results. b The effect of polyvinylpyrrolidone (PVP) concentration (PVP conc) on the conductivity (σ) and relative conductivity (σ/σ_EGaIn) of activated LM. Bars show mean ± SD, and individual data points (n = 4) are overlaid. Relative change in resistance (ΔR/R₀) of activated LM ink (LMI) line under c twisting, d bending, and e stretching, with insets showing photographs of the corresponding deformations. The gauge factor (GF) was extracted from the slope of a linear fit. f Cyclic signals under subtle strain. g Response and recovery times under 0.5% tensile strain. h Cyclic signals at stretch rates of 1.5–19.5 mm/s (0.05–0.65 Hz) under 50% tensile strain. i ΔR/R₀ during 350 cycles of 50% strain, with insets showing magnified signals from 5 stretching cycles in the periods of 209–241 s and 2540–2577 s. Source data are provided as a Source data file.