多層涂層的抗氧化性能
(1. 中南大學(xué) 材料科學(xué)與工程學(xué)院，長(zhǎng)沙 410083；
2. 株洲鉆石切削刀具股份公司，株洲 412007)
摘 要: 對(duì)化學(xué)氣相沉積(CVD)法制備的硬質(zhì)合金TiN/TiCN/Al2O3/TiN多層涂層試樣在600~950 ℃溫度范圍內(nèi)進(jìn)行了氧化質(zhì)量增加試驗(yàn)，采用X射線衍射(XRD)和掃描電子顯微鏡(SEM)分析試樣氧化前后相組成及微觀組織。結(jié)果表明：復(fù)合涂層最外層為α-Al2O3時(shí)，涂層具有最佳的抗氧化能力；增加TiN/TiCN/κ-Al2O3/TiN復(fù)合涂層中TiCN和κ-Al2O3的厚度能大大提高涂層高溫抗氧化性。TiN和TiCN涂層經(jīng)600 ℃以上氧化后，產(chǎn)物均為金紅石結(jié)構(gòu)的TiO2，氧化后TiN/TiCN間的界面消失；經(jīng)900 ℃以上氧化時(shí)，κ-Al2O3轉(zhuǎn)變?yōu)棣?Al2O3。
關(guān)鍵字: 硬質(zhì)合金；化學(xué)氣相沉積多層涂層；抗氧化性
coatings on cemented carbide by chemical vapor deposition
（1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Zhuzhou Cemented Cutting Tools Co., Ltd., Zhuzhou 412007, China）
Abstract:The oxidation mass gain test at the temperature range of 650−950 ℃ in different times were carried out on the cemented carbide coated by multilayer TiN/TiCN/Al2O3/TiN coating prepared by chemical vapor deposition (CVD) method. The phase component and microstructure of coating samples were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that, when the outset layer is α-Al2O3, the sample exhibits excellent oxidation resistance. The oxidation resistance of TiN/TiCN/κ-Al2O3/TiN multilayer coating sample is improved with the increase of the thickness of TiCN and κ-Al2O3. The oxidation product of TiN and TiCN layer is rutile TiO2 when the temperature is higher than 600 ℃, and the interface of TiN/TiCN disappears. The κ-Al2O3 transforms to α-Al2O3 when the oxidation temperature is above 900 ℃.
Key words: tungsten carbide; chemical vapor deposition multilayer coatings; oxidation resistance
