Extended Data Fig. 4: Materials and nozzle geometry for springy filaments and lattices.
From: Rotational multimaterial printing of filaments with subvoxel control
a–c, Tensile testing of cured soft, stiff and mixed acrylic base materials. a, Stress–strain curves for N = 17 tensile tests for cured soft acrylic (Young’s modulus = 0.52 ± 0.03 MPa; mean ± s.d.), used as both the dielectric elastomer ink in the HDEAs and as the soft structural ink in the springy filaments. b, Stress–strain curves for N = 9 tensile tests for cured stiff acrylic (Young’s modulus = 2,700 ± 200 MPa; mean ± s.d.). c, Stress–strain curves for N = 11 tensile tests for a fully mixed combination of the stiff and soft acrylic base materials in a 50:50 volume ratio (Young’s modulus = 220 ± 20 MPa; mean ± s.d.). d,e, Fan-core geometry used in RM-3DP of springy filaments and lattices. d, Dimensions of nozzle tip overlaid on 3D model of nozzle tip. e, Ideal filament cross-section dimensions for Q* = 1 assume extruded inks extend to half of the wall thickness, dividing the fans from the fan-core. These dimensions were used to calibrate volumetric flow rates before printing.
