PCBN刀具切削GH706磨损特征研究

本文中采用PCBN刀具对镍基高温合金GH706车削试验研究刀具磨损并对比刀具材料.首先观察PCBN刀具的磨损形貌,根据其位置、形态等特点进行分类,分别为主切削刃边缘崩刃、主切削刃微崩刃及后刀面磨损、主副切削刃交界后刀面磨损、副切削刃微崩刃及副后刀面磨损等,从而将PCBN刀具磨损形式进行全新的定义,并根据刀具、工件属性以及切削过程刀-屑-工件相互作用特点,分析了不同类型磨损形成的原因.然后研究刀具磨损形貌随切削进程的变化规律,揭示了PCBN刀具切削GH706的失效历程.最后对比了5种不同PCBN材料的刀具的前、后刀面磨损状态,得到了CBN含量、结合剂种类对刀具磨损的影响规律,为高效切削镍基高温合金用PCBN刀具设计及应用提供技术指导.

PCBN Tool Wear Characteristic in Cutting Superalloy GH706

This paper presents tool wear and material comparison experiments of turning Ni-based superalloy GH706 with PCBN tools. Based on the characteristics of positions and states of PCBN tool wear,tool wear patterns are defined in a new way,e.g. notch wear on main edge border,chipping of the main cutting edge and flank wear,flank wear on the junction of main and minor cutting edges,minor flank wear and chipping on the minor cutting edge etc. The mechanisms of tool wear were presented according to the properties of PCBN and workpiece materials,and the relationship among tool,workpiece and chips. Also,this paper proposes the variation of tool wear and fracture in the cutting process in order to understand tool failure process. Finally,the relationships of tool wear with the CBN content and the binding agent are made clear through comparing five kinds of PCBN materials,which provides the technology supports for PCBN tool design and application.