Thermal management and process efficiency in thin-wall steel wire arc additive manufacturing: a comparison of dwell-time and interpass-temperature control strategies

Abstract Wire arc additive manufacturing (WAAM) enables large-scale metal deposition but is susceptible to thermal accumulation, which can affect geometric consistency and material response. This study experimentally compares fixed dwell-time and interpass-temperature-based thermal management in ER70S-6 steel thin-wall WAAM to evaluate their effects on thermal behavior, geometry, hardness, and production efficiency. Eight fixed dwell times (10–120 s) and five interpass-temperature setpoints (150–500 °C) were investigated using infrared thermography, geometric measurements, and Rockwell B hardness testing. Shorter dwell times and higher interpass temperatures increased thermal accumulation, producing wider, shorter walls and greater hardness variation. Increased cooling improved geometric consistency and hardness uniformity, with the largest changes occurring between approximately 40–60 s dwell and 300–200 °C interpass temperature. Beyond approximately 60 s dwell or below 200 °C, additional cooling produced comparatively smaller improvements while increasing production time. Both strategies limited thermal accumulation when sufficient cooling was provided, but temperature-based deposition adjusted dwell duration according to the measured thermal state rather than imposing a fixed interval. This direct comparison provides process-planning guidance for balancing dimensional consistency, hardness response, and production efficiency. The identified operating region is specific to the investigated material, geometry, and deposition conditions.