Influence of abrasive blasting on the surface roughness of metallic parts manufactured by atomic diffusion additive manufacturing (ADAM)

Purpose This study aims to enhance the limited understanding of how abrasive blasting influences surface roughness in metallic parts manufactured using atomic diffusion additive manufacturing (ADAM), a process known for producing inherently rough surfaces. Design/methodology/approach Four metal alloys − H13, A2, 17-4PH and Inconel 625 − were produced using the ADAM process and subjected to six abrasive media with varying Mohs hardness (2–9) and particle sizes (50–1000 µm). Surface roughness was evaluated using Ra, Rz, RSm and Rku, linked to performance in coatings, fatigue resistance, lubrication and finishing. Analysis of variance (ANOVA) and regression analyses were used to assess the impact of abrasive and material properties on roughness outcomes. Findings Abrasive selection strongly affects post-ADAM surface quality. Hard alumina (Mohs 9), glass beads (6), polymers (3) and walnut shell (2) were tested. In H13, alumina cut Ra by approximately 54%, glass by approximately 33%; in A2, glass lowered Ra by approximately 21% (top) and approximately 16% (side), walnut approximately 24% (top). In 17-4PH, alumina reduced Ra by approximately 20% (side); Inconel 625 showed approximately 28%–35% reduction with alumina, plus approximately 15% with glass (top). Effective Ra reduction may enhance finish, adhesion, fatigue resistance and lubrication potential. ANOVA confirmed abrasive type dominated (approximately 74% Rz, 70% Ra variance), while alloy type showed little effect. Originality/value This study systematically analyzes abrasive blasting in ADAM metals, linking abrasive traits to surface performance. It guides abrasive selection and parameters to enhance coating adhesion, fatigue resistance, lubrication and surface quality − offering practical strategies for postprocessing additively manufactured parts.