Wire Arc Additive Manufacturing (WAAM) has emerged as a cost-effective and high-deposition-rate technique for fabricating large-scale metallic components; however, the complex thermal history inherent to the process leads to heterogeneous microstructures that can significantly influence tribological performance. In this study, the dry sliding wear behavior of WAAM-fabricated austenitic stainless steel 308L (SS308L) was systematically investigated using a pin-on-disk configuration. The influence of applied normal load (1.5–15 N) and sliding speed (0.03–0.229 m/s) on wear volume, specific wear rate, coefficient of friction (COF), and tangential force was evaluated. Optical microstructural observations indicated features consistent with a ferritic–austenitic solidification structure, including regions resembling polygonal ferrite, Widmanstätten ferrite, and austenitic dendritic morphologies. Wear results showed that wear volume and cross-sectional area increased monotonically with increasing load, while the effect of sliding speed was comparatively less significant. The specific wear rate remained on the order of 10⁻⁴ mm³/N·m with minor variations across test conditions. The COF decreased with increasing load up to 10 N, followed by a speed-dependent response at higher loads. The findings demonstrate that load is the dominant factor governing wear behavior in WAAM SS308L, while microstructural heterogeneity may contribute to frictional stability and wear resistance. This study provides valuable insight into the structure–tribology relationship of WAAM stainless steels and supports the optimization of process parameters for wear-critical applications.

Additive manufacturing (AM) of stainless steel has been gaining industry attention in recent years due to the need to manufacture complex steel components. Many sectors stand to benefit from the design flexibility, customization, and rapid production capabilities of AM. However, the industry’s adoption of this technology remains limited due to concerns about the mechanical integrity and reliability of AM products. This experimental study examines the wear and tribological behavior of Wire Arc Additive Manufactured (WAAM) austenitic stainless steel 316L. Pin-on-disk tests were conducted using a 5 mm tungsten carbide ball under dry sliding conditions at normal loads of 1.5 and 2.5 N and sliding speeds between 0.03 and 0.229 m/s. The results showed that the coefficient of friction remained relatively stable at approximately 0.6, while wear volume generally decreased with increasing sliding speed. Lower normal loads resulted in lower wear volume, whereas the wear factor showed only limited sensitivity to the applied load. Optical microscopy revealed a ferrite–austenite microstructure with residual δ-ferrite that contributes to the observed wear behavior. These findings demonstrate the suitability of WAAM-produced 316L stainless steel for tribological applications requiring stable frictional performance.

Fused Deposition Modeling (FDM) offers manufacturing flexibility for acrylonitrile butadiene styrene (ABS), but mechanical performance is sensitive to thermal history during printing. This study examines the effects of printing temperature (PT), chamber temperature (CT), and cooling fan speed (CFS) on the tensile properties of FDM-printed ABS. A face-centered central composite design (75 specimens, 15 conditions, five replicates) was used to fit second-order models for ultimate tensile strength (UTS), tensile toughness (T, calculated as the area under the stress–strain curve up to fracture), and break strain (${\epsilon }_B$). PT was the dominant factor for all three responses (15–29% of total variance), with lower PT yielding higher strength, toughness, and ductility. A significant chamber-temperature × cooling-fan-speed interaction was identified for UTS ($F=9.13$, $p=0.004$), requiring joint optimization for strength. CT had no statistically significant effect on toughness or break strain, either alone or in interaction, within the tested range. Single-response optimization identified PT = 220 °C, CT = 42 °C, CFS = 50% as maximizing UTS (29.6 MPa); the point estimates for toughness and break strain were nominally higher at CT = 58 °C, but a formal contrast between CT = 42 and 58 °C showed 95% confidence intervals that included zero for both responses, so this difference cannot be resolved from noise. PT = 220 °C and CFS = 50% are robust recommendations across all models and weightings tested, while the optimal CT for toughness and break strain remains unresolved within this design. These findings provide a statistically grounded framework for selecting thermal process parameters for FDM-printed ABS components.