分别用高速钢刀具、硬质合金刀具和Si3N4陶瓷刀具对氟金云母可加工陶瓷进行车削加工试验,考察了氟金云母陶瓷车削加工中刀具的磨损过程、磨损形态及失效原因。SEM电镜观察和能谱分析表明,刀具磨损主要发生在后刀面和刀尖处,刀具磨损的主要形式有磨料磨损、粘结磨损,材料高硬度、低热导率是引起刀具磨损的主要原因。刀具破损的主要形式为高速钢刀具切削刃塑性变形和陶瓷刀具的崩刃。刀具与工件的组织不均匀,以及切削过程中产生的冲击性机械应力和热应力是刀具破损的主要原因。
The machinable fluorophlogopite was turned with tools made by tungsten-cobalt carbide, high-speed steel and ceramics respectively. The processes, modes and causes of tool wear were analyzed through turning fluorophlogopite glass-ceramics. The results show the tool wear occurred on flank and corner through observing wear feature with SEM and analysising of the spectra. The modes of tool wear include abrasive wear and adhesive wear. The main causes of tool wear are high hardness and lower thermal conductivity of fluorophlogopite. The modes of tool damage include plastic deformation on cutting edge of high-speed steel tool and tipping of ceramics tool. The factors caused the tool damage are uneven texture of tools and workpieces, impactful mechanical stress and thermal stress during cutting of fluorophlogopite.