%0 Journal Article
%4 sid.inpe.br/mtc-m21b/2016/04.11.17.15
%2 sid.inpe.br/mtc-m21b/2016/04.11.17.15.05
%@doi 10.1088/2053-1591/3/2/025601
%@issn 2053-1591
%T Nano- And microcrystalline diamond deposition on pretreated WC-Co substrates: Structural properties and adhesion
%D 2016
%8 Feb.
%9 journal article
%A Fraga, Mariana Amorim,
%A Contin, André,
%A Rodríguez, L. A. A.,
%A Vieira, J.,
%A Campos, R. A.,
%A Corat, Evaldo José,
%A Trava Airoldi, Vladimir Jesus,
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Universidade Federal de São Paulo (UNIFESP)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Universidade Federal de São Paulo (UNIFESP)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@electronicmailaddress fraga.mariana80@yahoo.com.br
%@electronicmailaddress andre.contin@las.inpe.br
%@electronicmailaddress
%@electronicmailaddress
%@electronicmailaddress
%@electronicmailaddress evaldo.corat@inpe.br
%@electronicmailaddress vladimir.airoldi@inpe.br
%B Materials Research Express
%V 3
%N 2
%P 025601
%K Adhesion, Brazilian MRS, Diamond, Seeding, Wc-co substrate.
%X Many developments have been made to improve the quality and adherence of CVD diamond films onto WC-Co hard metal tools by the removing the cobalt from the substrate surface through substrate pretreatments. Here we compare the efficiency of three chemical pretreatments of WC-Co substrates for this purpose. First, the work was focused on a detailed study of the composition and structure of as-polished and pretreated substrate surfaces to characterize the effects of the substrate preparation. Considering this objective, a set ofWC-9%Co substrates, before and after pretreatment, was analyzed by FEG-SEM, EDS and x-ray diffraction (XRD). The second stage of the work was devoted to the evaluation of the influence of seeding process, using 4 nm diamond nanoparticles, on the morphology and roughness of the pretreated substrates. The last and most important stage was to deposit diamond coatings with different crystallite sizes (nano and micro) by hot-filament CVD to understand fully the mechanism of growth and adhesion of CVD diamond films on pretreated WC-Co substrates. The transition from nano to microcrystalline diamond was achieved by controlling theCH4,/H2, gas ratio. The nano and microcrystalline samples were grown under same time at different substrate temperatures 600 °C and 800 °C, respectively. The different substrate temperatures allowed the analysis of the cobalt diffusion from the bulk to the substrate surface during CVD film growth. Furthermore, it was possible to evaluate how the coating adhesion is affected by the diffusion. The diamond coatings were characterized by Raman spectroscopy, XRD, EDS, FEG-SEM, atomic force microscope and 1500 NRockwell indentation to evaluate the adhesion.
%@language en
%3 Fraga_nano.pdf