Machinability of the laser additively manufactured Inconel 718 superalloy in turning

In industrial fields, subsequent machining processing is essential for the laser additively manufactured (LAM) parts to meet the requirements of dimensional accuracy and surface quality in practical applications. Compared with the wrought Inconel 718 superalloy, this research investigated the machinability of the direct laser metal sintered Inconel 718 superalloy. The results indicated that the LAM Inconel 718 superalloy had irregular continuous chips with serrated edges and uncontrollable outflow, small cutting force and cutting vibration due to the poor density of 8.1577 g/cm(3) and small microhardness up to 412 HV0.2, and low cutting temperature owing to the high thermal conductivity of 24.7 W/(m center dot K). The coated carbide tools were suitable for the cutting of the LAM Inconel 718 superalloy. The cutting force, cutting temperature, and cutting vibration of the LAM Inconel 718 superalloy obtained with the coated carbide tools were about 9.63, 6.29, and 16.67% smaller than those of the wrought Inconel 718 superalloy, respectively. The coated carbide tools presented a longer average life of 12.41 min with crater wear, notch wear, and nose breakage in the cutting of the LAM Inconel 718 superalloy, while a shorter life of 3.28 min with crater wear and nose wear in the cutting of the wrought Inconel 718 superalloy, and obtained similar surface roughness of the machined LAM and wrought Inconel 718 superalloys.