Experimental and Numerical Investigation of Thermally Activated Shape-Morphing in 4D-Printed ABS Beams

This study investigates the thermally induced shape-morphing behavior of 4D-printed beams fabricated from Acrylonitrile Butadiene Styrene (ABS) using fused deposition modeling (FDM). A comprehensive experimental methodology was employed to examine the influence of key process parameters—namely printing speed, layer height, layer width, nozzle temperature, and activation temperature—on the deformation characteristics of the printed structures. A Taguchi design of experiments was combined with signal-to-noise ( S/N ) ratio analysis and analysis of variance (ANOVA) to identify optimal parameter settings and quantify their statistical significance. Empirical analytical models were proposed through multiple linear regression to describe the relationships between process parameters and shape-morphing responses. To complement the experimental analysis, a finite element model was developed, incorporating layer-specific coefficients of thermal expansion ( CTE s) to simulate the differential thermal contraction across the printed layers. Comparison between simulated and experimental results showed good agreement, validating the modeling approach. The integrated experimental–statistical–numerical framework presented in this work provides practical insights for optimizing shape-morphing behavior in 4D-printed thermoplastic structures and demonstrates the potential of ABS as a viable material for time-responsive applications.