Load-Dependent Instrumented Indentation Test and Local Micromechanical Response near a Pore in Additively Manufactured IN718

In this work, the load-dependent indentation response of as-built Inconel 718 produced by direct laser deposition was studied, followed by local mapping around a single surface-intersecting pore. A working load of 100 mN was selected because the indentation modulus approached a depth-independent plateau and the penetration depth was substantially larger than the measured surface roughness. At this load, the reference matrix response was HIT = 2.69 ± 0.26 GPa and EIT = 160 ± 11 GPa. An equivalent contact radius ac was calculated from the projected contact area, and pore-edge distance was normalized as ξ = s/ac. For the reference response, ac ≈ 3.44 µm and the first numerically defined position at s = 20 µm corresponded to ξ ≈ 5.8. Robust regression of 56 individual measurements showed no statistically resolved dependence of EIT on ξ, whereas a small negative HIT slope was observed and interpreted cautiously because of directional variability. The analysis is restricted to this single pore and to ξ ≥ 5.8; the immediate pore-edge regime was not experimentally resolved. The contact-scale normalization provides a reproducible framework for interpreting local indentation data near a geometrical defect without treating the two-dimensional pore-area fraction as bulk porosity.