(武漢工業(yè)大學(xué) 材料復(fù)合新技術(shù)國(guó)家重點(diǎn)實(shí)驗(yàn)室， 武漢 430070)
摘 要: 采用自制2 450 MHz, 5 kW不銹鋼諧振腔型微波等離子體設(shè)備， 研究了超聲處理、 細(xì)砂紙研磨、 1 μm和0.5 μm金剛石粉研磨等Si3N4 基底預(yù)處理方法對(duì)MPCVD金剛石涂層質(zhì)量的影響， 用SEM和Raman光譜儀檢測(cè)和分析了金剛石成核和生長(zhǎng)質(zhì)量， 分析了金剛石的應(yīng)力情況， 用對(duì)比切削實(shí)驗(yàn)檢測(cè)了金剛石涂層的附著情況。 結(jié)果表明，經(jīng)0.5μm金剛石粉研磨后， 在7.0kPa壓力、 1.5%的CH4/H2氣體流量比、1.5 kW微波功率下， 沉積4 h可得到高質(zhì)量的金剛石涂層， 在切削18.0%SiAl合金時(shí)， 金剛石涂層Si3N4刀具比未涂層Si3N4刀具的加工光潔度提高一級(jí)， 使用壽命提高10倍以上。
關(guān)鍵字: 金剛石涂層； 微波等離子CVD； Si3N4基底；干切削
（State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, P.R.China）
Abstract:The effects were studied of Si3N4 tool substrate pretreatment in ultrasonic, polishing of fine gained SiC emery paper, 1.0 μm and 0.5 μm diamond powder on the quality of MPCVD diamond coating in a domestic 2 450 MHz, 5kW stainless steel resonant cavity microwave plasma CVD (MPCVD) equipment. The qualityof diamond nucleation and growth was measured, then the stress condition was analysed, at last the adhesion of diamond coating in contrast cutting test was determined. The results show that high quality diamond coating can be obtained under 4 h MPCVD with 7.0 kPa pressure, 1.5%CH4/H2 gas volume rate, 1.5 kW microwave power after pretreatment of 0.5 μm diamond power polishing, diamondcoated Si3N4 tool can increase its precision about one order compared with uncoated Si3N4 tool when it cut the 18.0%SiAl alloy, moreover, the service life of diamondcoated tool increases by 10 times.
Key words: diamond coating； microwave plasma CVD； Si3N4 substrate； dry cutting
