Experimental Study on Cutting Edge Preparation of Zirconia-Toughened Aluminum Oxide Ceramic Inserts Using Abrasive Brushing Tools

In this study, the material removal behavior of abrasive brushing tools on zirconia-toughened alumina cutting edges is experimentally investigated. Three different brushing tool specifications with bonded diamond grains are tested, varying in filament diameter, filament length, and grain size. Using an industrial robot setup, structured brushing experiments are performed on the cutting edges of indexable inserts under controlled variations of key process parameters, such as brushing velocity vb, axial feed rate vfa, infeed ae, and contact angle φ. The resulting edge rounding is quantified using three-dimensional optical scanning. Key metrics, such as edge radius rβ and form factor K, are evaluated to assess the suitability of abrasive brushing processes for the preparation of ceramic cutting edges. The results showed that the edge radius ranged from rβ = 20 to 80 µm, while the form factor varied from K = 1 to 3. The brushing velocity vb and axial feed rate vfa were identified as the primary parameters influencing the rounding radius rβ, whereas the infeed ae was the dominant parameter affecting the form factor K. While cutting edge preparation of metal and carbide tools is well studied, little research exists on abrasive brushing of zirconia-toughened alumina (ZTA) cutting inserts. Because ZTA behaves differently from metals, this study systematically investigates robot-assisted abrasive brushing of ZTA, analyzing how key process parameters affect edge radius, shape, and uniformity along the cutting edge.