| Two machinable ceramics, ZrO2/CePO4 and fluorophlogopite, werechosen for cutting test. During turning and drilling, the process of materialremoval and tool wear were analysed. Material removal mechanism and toolwear modes were studied through SEM observations. With single-factor tests,the influences of machining conditions on material removal and tool wearwere studied.Material removals of two ceramics contain two modes, transgranularfracture and intergranular fracture. In drilling ZrO2/CePO4 ceramics, theprocess of material removal can be divided into high material removal rateperiod and high tool wear period. However, in cutting fluorophlogopite, theprocess of material removal can be divided to initial period, stable period andterminal period.In drilling ZrO2/CePO4 ceramics, the process of tool wear can be dividedinto beginning and terminal periods. The beginning is a normal period and theterminal is a quick wear period. In cutting fluorophlogopite, the process oftool wear can be divided to beginning, stable and immoderate wear period.In drilling, wear of drill bits usually occurs on major flank, minor flankand chisel edge. In the fluorophlogopite turning, wear of tools usually occurson major flank and tool corner. Abrasive wear and adhesive wear are commonphenomena. The main disrepair mode is oxidation wear in drillingZrO2/CePO4. However, the main rupture modes are plastic deformation ofcutting edge, flaw, scaling, fragmentation and pock on cutting edge.Distributing hard particles in fluorophlogopite, the mechanical and thermalvibrancy, and low thermal conductivity cause the invalidation of drill bits.The machining conditions affect material removal and tool wear, such astool materials, cooling condition, cutting parameter and tool angles.Especially, the tool materials and cooling conditions are the major factors.The tool material and machining parameters should be optimized toobtain low tool wear and high machining efficiency in cutting machinableceramics.
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