Effects of tool wear on cutting force, cutting temperature and surface integrity characteristics during milling of ATI 718Plus superalloy

As a novel high-temperature alloy, ATI 718plus exhibits outstanding performance under operating conditions ranging from 650 °C to 750 °C. This study investigates the impact of tool wear on the material properties of ATI 718plus during machining, using a combination of experimental and simulation methods to analyze its effect on the surface integrity of workpiece during milling. The experimental results show that the tool wear process can be categorized into three stages: initial, stable, and severe. As tool wear progresses, milling force increases significantly; specifically, when the width of the flank wear land (VB) increases from 0 μm to 335 μm, the milling force nearly triples. Surface roughness in the milling width direction increases by approximately 2.5 times. Tool wear also leads to a reduction in residual compressive stress levels while increasing residual tensile stress levels. Moreover, the surface microhardness rises from 509.41 HV_0.025 to 539.7 HV_0.025, and the depth of the plastic deformation layer in the workpiece increases from 4 μm at VB = 0 μm to 8.5 μm at VB = 335 μm. These findings are significant for effectively managing tool wear and enhancing the milling quality and surface integrity of ATI 718plus alloy.