Structure, Properties and Fabrication of the Solid Nanocrystalline Coatings Deposited in Several Ways

Investigation of the structure and physicochemical properties of combined nanocomposite coatings based on Ti–N–Cr/Ni–Cr–B–Si–Fe

“…This suggests that to increase the resistance to elastic failure strain and to decrease the plastic strain, a material must have high hardness at a low elastic modulus. The parameter Н 3 /Е 2 for ceramics and ceramic metals is known to be not over 0.2 GPa, whereas, for instance, for TiNi it is an order of magnitude lower (due to the shape memory effect) [5]. The new combined composite coatings obtained show the Н 3 /Е 2 parameter values about 0.32 ± 0.02.…”

“…The morphology and element composition analyses were performed with a REMMA-103M scanning electron microscope equipped with a microanalyzer by using the energy dispersion (EDS) and wave dispersion spectra (WDS). The structure and the phase composition were examined on an Advance-8 (XRD analysis) facility (including a sliding beam starting from 0.5°) [6]. Microanalysis was also performed with a LEO-1455R scanning electron microscope.…”

“…The thin and thick coatings were scanned throughout the metallographic section width. Some thick coatings subject to microanalysis were subject to plasma-jet melting and the other were unmelted [6].…”

“…It has been shown [6][7][8][9][10][11] that the combined and hybrid coatings based on Al 2 O 3 /Cr/TiN and Al 2 O 3 /TiN, which were examined before and after electron beam treatment, changed (improved) some service characteristics, such as resistance to wear, adhesion, corrosion resistance, and temperature stability (to 950°C) when γ-phase was formed, and that coatings could be temperature stable up to 2000°С when Al 2 O 3 α-phase was formed. It has been found [13,14] that coatings based on Ni-Cr (Fe, Si, B) deposited on steel (or steel articles) improve the hardness, resistance to wear, corrosion resistance, and adhesion, and these characteristics are further improved on subsequent melting of the coating with an electron beam or a plasma jet.…”

“…Physically, the nanostate arises due to size effects by which is meant a complex of phenomena associated with the changes in the material properties that occur when the microstructure block size becomes equal to some critical length characterizing the phenomenon (the free paths of electrons and phonons, the thickness of domain walls, the critical radius of the dislocation loop, etc.) [1][2][3][4][5].…”