OPTIMIZATION OF HEAT TREATMENT PARAMETERS FOR MECHANICAL STRENGTH AND SURFACE QUALITY OF FDM-PRINTED ABS

Vollständiger Abstract

Worum geht es in dieser Arbeit?

Fused Deposition Modeling (FDM) of ABS is a cost-effective and versatile additive manufacturing technique; however, it is often constrained by residual stresses and poor surface finish, limiting its applicability in dimensionally critical components. Controlled heat treatment as a post-processing approach can relieve internal stresses and improve interlayer bonding, yet its combined effect on dimensional accuracy, mechanical performance, and surface quality remains insufficiently quantified. In this study, an experimental study combined with statistical analysis was conducted to investigate the effects of annealing temperature (100–140 °C) and holding time (20–60 min) on the dimensional stability, tensile strength, and surface roughness (Ra) of FDM-printed ABS specimens. Dimensional changes were expressed through the Dimensional Stability Index (DSI), tensile properties were measured according to ASTM D638, and surface roughness was characterized via contact profilometry. A Response Surface Methodology (RSM) approach coupled with Analysis of Variance (ANOVA) was employed to model and interpret the parameter effects. The results showed that temperature is the dominant factor influencing both DSI and tensile strength. The DSI values were minimal at 100 °C, showed moderate dimensional deviation at 120 °C, and increased sharply at 140 °C, demonstrating pronounced warpage and shrinkage near higher annealing temperatures. Tensile strength increased from 26.74 MPa in the untreated condition to a maximum of 30.82 MPa after annealing at 140 °C for 60 min, corresponding to a 15.3% improvement. In contrast, holding time showed a comparatively minor influence within the studied range. Although the minimum Ra was 4.72 µm at 120 °C for 40 min, representing a 30.1% decrease compared with the untreated specimens, surface roughness showed no statistically significant dependence on temperature or time. These findings demonstrate that controlled annealing can substantially enhance the mechanical performance of FDM-printed ABS parts, while moderate temperatures are preferable when dimensional accuracy must be preserved.