摘要 通過(guò)切削實(shí)驗(yàn)，觀察切削前后刀具的表面和刃口形貌、金剛石刀片組成成分、以及被加工工件表面粗糙度，比較兩種刀具的切削性能，探討其失效機(jī)理。結(jié)果表明：在同等條件下，CVD金剛石刀具的切削性能要明顯優(yōu)于PCD刀具。在車(chē)削過(guò)程中，PCD刀具的失效機(jī)理主要是結(jié)合劑與被加工材料中化學(xué)成分發(fā)生化學(xué)反應(yīng)使結(jié)合劑流失，導(dǎo)致刀具結(jié)構(gòu)疏松，從而導(dǎo)致磨粒團(tuán)脫落。CVD刀具的失效機(jī)理為產(chǎn)生變質(zhì)層磨損。切削過(guò)程中隨著加工時(shí)間的進(jìn)一步延長(zhǎng)，切削區(qū)溫度不斷升高，當(dāng)達(dá)到熱化學(xué)反應(yīng)溫度時(shí)，就會(huì)在刀具表面形成變質(zhì)層，從而帶來(lái)切削過(guò)程中刀具的磨損；同時(shí)高溫狀態(tài)下CVD金剛石的晶界疲勞破壞，也可能會(huì)造成CVD金剛石刀具的磨損失效。(金剛石與磨料磨具工程2009年第一期)
　　
　　Abstract Cutting experiment on hard plastic PMMA was conducted with PCD and CVD cutter respectively．The edge and surface morphology and composition of the PCD and the CVD diamond insert，as well as the surface roughness，were studied before and after the cutting process．The cutting performance of these tools was compared and their failure mechanism was explored．The results showed that under the same machining condition，the cutting performance of the CVD diamond tools was superior to that of the PC D tools．The main failure mechanism of the PC D tools is the chemical reaction between binder and machined material，which leads to the loss of binder and the abscission of worn particles(diamond particles)，and then induces the damage of the cutting tools structure．The failure mechanism of the CVD diamond tools is the wear of affected layer．With further extension of the cutting process，the temperature of the cutting zone keeps rising．When the temperature reached the thermal chemical reaction temperature，affected layers would be generated at the tool surface as the insert abraded out；at the same time，the tools’wear may also be caused by the fatigue failure of the grain boundary of CVD diamond at high temperature．