Assessment of surface roughness, dimensional accuracy, and hardness in 17-4PH stainless steel standardized artifacts manufactured by atomic diffusion additive manufacturing

Abstract

Additive manufacturing offers significant advantages over conventional technologies and continues to expand in the industrial sector through the incorporation of metallic materials. However, certain aspects, such as surface finish and dimensional accuracy, still lag behind those achieved by CNC subtractive technologies. Several technologies, including material extrusion (MEX) and powder bed fusion (PBF), enable the use of metallic feedstock. Previous studies have analyzed surface finish, mechanical strength, and dimensional accuracy, but they often rely on disparate manufacturing parameters and non-standardized test artifacts. This study presents the characterization of dimensional accuracy, surface roughness, and hardness in parts produced by the material extrusion technology known as Atomic Diffusion Additive Manufacturing (ADAM), using 17-4PH stainless steel as feedstock. The characterization was performed using standardized artifacts in accordance with ISO/ASTM 52902:2019, facilitating effective comparisons between metallic additive manufacturing technologies through a consistent dimensional study. The results revealed absolute dimensional deviations, for various geometric elements ranging from -0.23 to 0.74 mm, and percentage deviations ranging from -4.6% to 1.58%, depending on the geometry. The influence of build orientation on dimensional deviations was also evaluated, along with roughness (3.66 ± 1.23 µm for horizontal geometries) and hardness varied with inclination angle, ranging from 27.6 ± 2.1 HRC to 33.0 ± 1.7 HRC for angles up to approximately 60°. Finally, a concise metallographic analysis is presented to illustrate the internal structure of the parts