Investigation of the Nature of the Interaction of Me-MeN-(Me,Mo,Al)N Coatings (Where Me = Zr, Ti, or Cr) with a Contact Medium Based on the Ni-Cr System

Abstract

This paper discusses the results of a study focused on the nature of the interaction of Me-MeN-(Me,Mo,Al)N coatings (where Me = zirconium (Zr), titanium (Ti), or chromium (Cr)) with a contact medium based on the Ni-Cr system. The studies were carried out during the turning of nickel–chromium alloy at different cutting speeds. The hardness of the coatings was found, and their nanostructure and phase composition were studied. The experiments were conducted using transmission electron microscopy (TEM), X-ray diffraction (XRD), and selected area electron diffraction (SAED). According to the studies, at elevated cutting speeds, the highest wear resistance is demonstrated by the tools with the ZrN-based coating, while at lower cutting speeds, the tools with the TiN- and CrN-based coatings had higher wear resistance. At elevated cutting speeds, the experiments detected the active formation of oxides in the ZrN-based coating and less active formation of oxides in the CrN-based coating. No formation of oxides was detected in the TiN-based coating. The patterns of cracking in the coatings were also studied.

Technologies of Coatings and Surface Hardening: Industrial Applications

“…It was shown in [21] That may indicate the process of tribooxidation under the influence of probable increased mechanical and thermal loads (turning Ni-based alloys) and create conditions for increased lubricity [28]. There is supposed to be a dependence between the protective transition oxide layer that exhibits thermochemical inertness and phase stability up to ~1200 • C for ZrO 2 (zirconium dioxide is polymorphic-when heated up to ~1200 • C, it changes from monoclinic phase m-ZrO 2 to tetragonal one t-ZrO 2 by a martensitic mechanism with volumetric changes up to ~5%-9%; upon further heating to 2300 • C, it diffusional passes into the cubic phase c-ZrO 2 ) and more than ~1000 • C for chromium trioxide CrO 3 (different oxidation states of chromium are achieved by calcination, CrO 3 → Cr 2 O 3 → CrO) and the depth of nickel diffusion [29][30][31].…”

“…The product's operational life can be improved via introduced innovations in the coating and surface layer structure deposed to such materials as high-speed tool steel [16], Al 2 O 3 + TiC ceramic [17,18], Si and hard alloy substrate [19][20][21][22][23][24][25], plastic substrate [26]. The innovative multilayer coatings demonstrate the destruction of the coating from the contact load passing through one layer and developing along the interface between the layers, significantly increasing the product's durability [19][20][21][22][23][24][25]. At the same time, nanocomposite coatings containing the amorphous phase with the introduced nano-crystallines of 3-5 nm hamper the development of the cracks and redirect them [23,24].…”

“…The interlayer introduced in the coating also improves its durability by improving coating adhesion [17,19,23]. Some of the coatings exhibit a self-healing effect under mechanical and thermal loads-with reaching a contact temperature of 800-1000 • C, some of the coating components may oxidize and form amorphous phases that can provide superlubricity in the processing zone and increase the operational life of the cutting tool [16,21,23]. Thin oxide films of a few nanometers effectively hamper moisture and protect microelectronics from mechanical and thermal loads [26].…”

“…Properties including high-temperature and triboproperties of the advanced multi- [19][20][21][22][23][24][25] and mono-layer [16,17], nanocomposite [23,24], nanostructured [18], and nanothin coatings [26];…”

“…Coating technologies such as physical vapor deposition (PVD) [17,23,24,27], including a radio frequency magnetron sputtering [16], high-power impulse magnetron sputtering [18], a closed-field unbalanced magnetron sputtering [19,20], filtered cathodic vacuum arc deposition [21,22,25], as well as atomic layer deposition [26]; • Full-scale tests in conditions close to industrial ones in milling hardened steel 100CrMn6 [17] and titanium alloys [23], turning steel 1045 [22], nickel-chromium alloy [21,25], and ironnickel alloy [24], annealing tests [19,20], open/short tests for electronic components [26]; • Development of a mathematical basis for future research [23,24].…”