【摘要】： 在硬質(zhì)合金工具或部件表面沉積金剛石薄膜,可以大幅度提高工具或部件的耐磨性,延長其使用壽命,進(jìn)而提高生產(chǎn)效率,但是金剛石薄膜與硬質(zhì)合金基體間粘附性不足的問題制約了其應(yīng)用。本論文采用氫氣、甲烷和四甲基硅烷(TMS)混合氣體作為反應(yīng)氣體,用熱絲化學(xué)氣相沉積法在硬質(zhì)合金(WC-6wt.% Co)基體上沉積金剛石-碳化硅-硅化鈷復(fù)合薄膜,并將此復(fù)合薄膜作為中間層,以提高金剛石薄膜與基體的粘附性。采用掃描電子顯微鏡(SEM)、電子探針(EPMA)、X射線衍射(XRD)、拉曼光譜(Raman)和洛氏C壓痕法對薄膜的表面形貌、成分、結(jié)構(gòu)以及粘附性進(jìn)行了表征。 金剛石-碳化硅-硅化鈷復(fù)合薄膜中含有金剛石、β-SiC和硅化鈷(Co2Si、CoSi),在沉積過程中,金剛石和β-SiC晶粒競爭生長,硅化鈷的形成源于基體中Co的擴(kuò)散。金剛石-碳化硅-硅化鈷復(fù)合薄膜的成分和結(jié)構(gòu)可以通過調(diào)節(jié)氣相中TMS的濃度和偏流來控制。隨著TMS濃度的增加,膜中β-SiC含量增加,金剛石含量減少,且β-SiC和金剛石晶粒變小。正偏壓促進(jìn)金剛石的生長,并且增強(qiáng)金剛石的二次形核,隨著偏流的增加,膜中金剛石晶粒尺寸變大且含量增加,β-SiC含量減少。 頂層金剛石薄膜可以在TMS濃度較低(小于等于0.075%)的復(fù)合中間層上原位生長,是因?yàn)橹虚g層表面的金剛石晶粒沒有被SiC覆蓋。洛氏C壓痕實(shí)驗(yàn)表明金剛石-碳化硅-硅化鈷復(fù)合中間層可以提高金剛石薄膜與硬質(zhì)合金基體的粘附性。將金剛石-碳化硅-硅化鈷復(fù)合中間層經(jīng)過碳?xì)涮幚砗?進(jìn)一步提高了金剛石薄膜與硬質(zhì)合金基體的粘附性,復(fù)合中間層中的硅化鈷有利于提高金剛石薄膜與硬質(zhì)合金基體的粘附性。
[Abstract]:The deposition of diamond film on the surface of cemented carbide tools or components can greatly improve the wear resistance of tools or components, prolong their service life, and thus improve the production efficiency. However, the lack of adhesion between diamond film and cemented carbide substrate restricts its application. In this paper, the diamond-silicon-cobalt silicide composite films were deposited on cemented carbide (WC-6wt.% Co) substrates by hot-filament chemical vapor deposition with the mixture of hydrogen, methane and tetramethylsilane (TMS) as reaction gases. The composite film is used as the intermediate layer to improve the adhesion between diamond film and substrate. The surface morphology, composition, structure and adhesion of the films were characterized by scanning electron microscope (SEM),) (SEM), electron probe (EPMA), X diffraction (XRD), Raman spectroscopy (Raman) and Rockwell C indentation method. Diamond, 尾-SiC and cobalt silicide (Co2Si,CoSi) are contained in the diamond-silicon-cobalt silicide composite films. During the deposition process, diamond and 尾-SiC grains grow in competition. The formation of cobalt silicide originates from the diffusion of Co in the substrate. The composition and structure of diamond-silicon carbide cobalt silicide composite film can be controlled by adjusting the concentration and bias current of TMS in gas phase. With the increase of TMS concentration, the content of 尾-SiC in the film increases, the content of diamond decreases, and the 尾-SiC and diamond grains become smaller. The positive bias can promote the growth of diamond and enhance the secondary nucleation of diamond. With the increase of bias current, the grain size and content of diamond in the film increase and the content of 尾-SiC decreases. The top diamond films can be grown in situ on the composite interlayer with lower TMS concentration (less than 0.075%) because the diamond grains on the interlayer surface are not covered by SiC. Rockwell C indentation test shows that the interlayer of diamond silicon carbide and cobalt silicide can improve the adhesion of diamond film to cemented carbide substrate. The adhesion of diamond film to cemented carbide substrate was further improved after the interlayer of diamond, silicon carbide and cobalt silicide was treated with carbon and hydrogen. Cobalt silicide in the interlayer can improve the adhesion of diamond film to cemented carbide substrate.
【學(xué)位授予單位】：大連理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2010
【分類號】：TB383.2

【參考文獻(xiàn)】

相關(guān)期刊論文 前4條

1 劉沙,易丹青,余志明,盧斌,王建華,李泳俠,鄒丹;金剛石涂層用硬質(zhì)合金基體表面預(yù)處理研究新進(jìn)展[J];稀有金屬材料與工程;2001年05期

2 梁繼然,常明,潘鵬;熱絲CVD法制備金剛石膜[J];天津理工學(xué)院學(xué)報(bào);2005年01期

3 唐璧玉,靳九成;燈絲形變對金剛石薄膜沉積的影響[J];人工晶體學(xué)報(bào);1996年04期

4 王麗軍;金剛石薄膜CVD制備方法及其評述[J];真空與低溫;2000年02期

相關(guān)碩士學(xué)位論文 前1條

1 楊莉;硬質(zhì)合金/金剛石薄膜的制備和附著性能的研究[D];中南大學(xué);2004年

，

本文編號：2399754