Experimental study reveals enhanced fatigue strength in 3D-printed maraging steel via combined heat treatment, machining, and shot-peening, indicating optimal post-processing routes.
Key Points
To evaluate the fatigue performance of as-built direct metal laser sintered maraging steel and determine the effects of post-processing treatments, including heat treatment, machining, and micro-shot-peening.
Conducted experimental fatigue testing on additive-manufactured direct metal laser sintering (DMLS) Maraging Steel MS1 in both as-built and post-treated conditions.
Evaluated the individual and combined effects of post-processing interventions: aging heat treatment, surface machining, and micro-shot-peening.
Performed micrographic and fractographic analyses to inspect microstructure alterations and fracture surfaces.
Heat treatment enhanced fatigue strength by relaxing tensile residual stresses induced during the additive manufacturing process.
Micro-shot-peening introduced beneficial compressive residual stresses only when executed after, rather than prior to, machining operations.
Heat treatment and machining demonstrated a strong synergistic interaction, producing a magnified increase in fatigue resistance when implemented together.