Preparation and Structure of Chromium Coatings Doped with Diamond Nanoparticles Deposited Directly on a Monolithic Composite of Molybdenum and Aluminum

Electrochemical chromium coatings modified with nanodiamond particles were deposited directly on a monolithic composite with a layered structure. Diamond nanoparticles obtained by detonation synthesis were used. The chromium coatings were deposited on a monolithic composite with a complex structure based on molybdenum and aluminum alloys. This monolithic composite will be called “matrix” for short. X-ray diffraction analysis of the matrix and the coating was performed with powder X-ray diffractometer (XRD). Concentrations of nanodiamond particles of 10–15 g/L in the chromating electrolyte were used. Analyses of scanning electron microscope (SEM) of Bruker Inc. were performed. The microstructure was studied with a Polyx Met metallographic microscope at 200× magnification and ProgRes CT3 USB digital camera and a licensed ProgRes CapturePro software. The microhardness was measured using a PolyvarMet 4000 microhardness tester. In the chromium layer it is in the range 620–750 kg/mm 2 and in the matrix in the range 1000–1140 kg/mm 2 . The thickness of the chromium coatings with nanodiamond particles is between 45–50 µm.