Experimental investigation of micro-milling of AISI 310 fabricated by selective laser melting

Selective laser melted (SLM) components have complex microstructures and surface features, posing specific challenges to micro-milling. This work explores the influence of micro-milling process factors and the feed direction on the machinability characteristics of SLM 310. Experimental findings confirm that the process parameters are important in achieving optimal surface roughness (Sa) and minimizing wear on the tool. Low feed rate and high spindle speed minimize flank wear. SEM and EDS analyses indicate that abrasive and adhesion wear are the predominant phenomena, with coating degradation contributing to wear progression. Burrs and Sa increase with rising feed rates but decrease with a rise in spindle speeds. Analysis of residual stress indicates differing compressive stresses, reaching a maximum of −517 MPa at 20,000 rpm with 60 mm/min feed rate. Machining at high speed with low feed minimizes tool wear, enhances surface quality, and provides steady micro-milling performance for SLM 310.