不同压力下硬质合金表面微波等离子体化学气相沉积SiC涂层规律性的研究  

Effect of Deposition Pressure on SiC Coatings Deposited by MPCVD on Cemented Carbide Substrates

作　　者：于盛旺[1] 黑鸿君[1] 胡浩林[1] 范朋伟[1] 张思凯[1] 唐伟忠[1] 吕反修[1] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083

出　　处：《人工晶体学报》2011年第4期876-881,共6页Journal of Synthetic Crystals

基　　金：省部产学研合作专项资金计划项目(2009A090100030)

摘　　要：以氢气和四甲基硅烷作为先驱气体,采用微波等离子体化学气相沉积法,不同沉积压力条件下、在YG6硬质合金表面制备了的SiC涂层。利用SEM、EDS、XRD、划痕测试法对SiC涂层的表面形貌、相组成和附着力进行了分析。实验结果表明,在较低的压力下,SiC涂层为胞状的纳米团聚物,且胞团的尺度随压力的升高而变小;随着压力的升高,胞状SiC开始并最终全部转变为片层状SiC,并在此过程中伴随着颗粒状Co2Si的形成与长大;随着压力的继续升高,片层状SiC开始转变为须状SiC。胞状SiC向片层状SiC的转变会使涂层致密度提高,而涂层对硬质合金衬底的附着力也会随之增强;Co催化作用的上升引起的片层状SiC向须状SiC的转变会导致SiC涂层的附着力明显降低。以具有片层状特征的SiC作为过渡层,可在未经去Co酸蚀预处理的硬质合金衬底上制备出具有较好附着力的金刚石涂层。SiC coatings were deposited on cemented carbide substrates by microwave plasma chemical vapor deposition method using tetramethylsilane（Si（CH3）4,TMS） diluted in H2 as the precursor.The morphology,phase composition and adhesion of the coatings were characterized by SEM,EDS,X-ray diffraction and scratching technique.The results show that at low pressures,the coatings are agglomerates of SiC nanoparticles,as the deposition pressure increasing,the size of the agglomerates decreases.As the pressure increasing,the agglomerates of SiC nanoparticles transforms to lamellar SiC,and at the same time Co2Si particles appear and grow larger.When the pressure increases further,the lamellar SiC would transform to whisker-like SiC.The density of coating increased as the SiC nanoparticles transformed to lamellar SiC.At the same time,the adhesion of the coatings enhanced as well.However,the adhesion of the coatings would be dramatically reduced when the lamellar SiC transforms to whisker-like SiC,as the surface Co atoms function as catalysts during such a transformation.It is proved that using the terrace-featured SiC coatings as transition layers,adhesion of diamond coatings to the cemented carbide substrates could be enhanced,without the use of the traditional acid etching procedure on the substrates.

关 键 词：SIC涂层 硬质合金 沉积压力 金刚石涂层 

分 类 号：O484[理学—固体物理]