EXPERIMENTAL STUDY OF CHROMIUM PVD COATINGS ON BRASS SUBSTRATES FOR THE WATCH INDUSTRY

摘要: Abstract Chromium coatings on brass substrates produced by the physical vapour deposition process with layer thicknesses of 0·3–5 μm have been investigated regard to structural, mechanical, and chemical properties coated system. The Cr layers a fine columnar structure crystallite size between 10 20 nm as determined X-ray measurements. conical shaped crystals made visible scanning tunnelling microscopy exhibit column diameters in range 20–60 at surface.The microhardness system under load HL was 15 000–25 000 MPa, twice high that substrate. In scratch test cohesive destruction observed critical values 0·1–0·4 N. corrosion tests stationary sputtering were mainly dense but occasionally slightly porous. anodic current density-potential curves for films (thickness ∼ 5 μm) are discussed comparison several othe...