Publication Date:
2019
Description:
〈p〉Publication date: 15 November 2019〈/p〉
〈p〉〈b〉Source:〈/b〉 Surface and Coatings Technology, Volume 377〈/p〉
〈p〉Author(s): A.P. Rubshtein, K. Gao, A.B. Vladimirov, S.A. Plotnikov, B. Zhang, J. Zhang〈/p〉
〈div xml:lang="en"〉
〈h5〉Abstract〈/h5〉
〈div〉〈p〉The structures, wear resistances, and corrosion behaviours of Cr–Al–C and multilayer [Cr–Al–C/a-C]〈sub〉〈em〉n〈/em〉〈/sub〉 coatings, fabricated by physical vapour deposition (PVD), plasma-assisted chemical vapour deposition (PACVD), or their combination, were studied. A Cr〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/sbnd"〉Al target served as a source of chromium and aluminium, while a graphite target or acetylene served as sources of carbon. Depending on the type of carbon source, Cr–Al–C or Cr–Al–C(H) coatings were obtained. Multilayer [Cr–Al–C/a-C]〈sub〉20〈/sub〉 and [Cr–Al–C(H)/a-C:H]〈sub〉20〈/sub〉 coatings were fabricated by alternating pair layers of [Cr–Al–C (PVD)/a-C (PVD)] and [Cr–Al–C(H) (PVD–PACVD)/a-C:H (PACVD)], respectively. a-C and a-C:H are hydrogen-free and hydrogenated diamond-like carbons. X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and Raman spectroscopy were employed to investigate the coating structures. Along with the amorphous matrix, chromium carbide, and Cr〈sub〉〈em〉x〈/em〉〈/sub〉Al〈sub〉1-〈em〉x〈/em〉〈/sub〉C nanograins, clusters of nanocrystalline graphite as spherical inclusions and plates, probably of several graphene layers, were observed in Cr–Al–C. This structure provided high hardness and corrosion resistance. Along with the amorphous matrix, Cr〈sub〉2〈/sub〉AlC and chromium carbide nanoclusters and clusters of nanoscale CVD diamond with wide boundaries of sp〈sup〉2〈/sup〉-bonded carbon were observed in Cr–Al–C(H), whose hardness did not exceed 8.9 GPa. The multilayer structures significantly increased the wear resistances. The specific coefficient of wear rate (SCWR) of [Cr–Al–C/a-C]〈sub〉20〈/sub〉 was five times lower than that of Cr–Al–C. Hybrid PVD–PACVD technology provided favourable conditions for the formation of wear-resistant coatings. The SCWR of [Cr–Al–C(H)/a-C:H]〈sub〉20〈/sub〉 was 47 times lower than that of [Cr–Al–C/a-C]〈sub〉20〈/sub〉. The high wear resistance of the multilayer coatings was associated with the structure, low friction coefficient, high crack resistance, and strengthened interface boundaries.〈/p〉〈/div〉
〈/div〉
〈div xml:lang="en"〉
〈h5〉Graphical abstract〈/h5〉
〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0257897219308849-ga1.jpg" width="232" alt="Unlabelled Image" title="Unlabelled Image"〉〈/figure〉〈/p〉〈/div〉
〈/div〉
Print ISSN:
0257-8972
Electronic ISSN:
1879-3347
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Permalink