Comparative Study of Sliding, Scratching, and Impact-Loading Behavior of Hard CrB2 and Cr–B–N Films

Сытченко

Pogozhev

et al. 2021

Materials

Coatings in a Zr-Mo-Si-B-N system were deposited by the magnetron sputtering of ZrB2-MoSi2 targets in argon and nitrogen. The structure of the coatings was investigated using scanning electron microscopy, X-ray diffraction, energy-dispersive spectroscopy, and glow-discharge optical emission spectroscopy. Mechanical and tribological properties were measured using nanoindentation and pin-on-disc testing. Oxidation resistance and oxidation kinetics were estimated via annealing in air at 1000–1500 °C and precision weight measurements. We found that the coatings deposited in Ar demonstrate a superior combination of properties, including hardness of 36 GPa, elastic recovery of 84%, a friction coefficient of 0.6, and oxidation resistance at temperatures up to 1200 °C. High oxidation resistance is realized due to the formation of the protective (SiO2 + ZrO2)/SiO2 oxide layer, which inhibits the diffusion of oxygen into the coating.

Section: Resultssupporting

confidence: 87%

Section: Introductionmentioning

confidence: 99%

Structure and Properties of Zr-Mo-Si-B-(N) Hard Coatings Obtained by d.c. Magnetron Sputtering of ZrB2-MoSi2 Target

Сытченко

Pogozhev

et al. 2021

Materials

“…All the coatings investigated in this work were characterized by a high friction coefficient when relatively soft material (steel 100Cr6, H = 8 GPa) was used as a counterpart. The surface of the coating is much harder (H = 12-30 GPa), and has high adhesion to steel, similar to [5]. The distinct behavior of coating 5 at the initial part of testing distance can be associated with the positive role of free carbon, which could be released owing to the oversaturation of the crystalline carbide phase and plays the role of a solid lubricant during friction [45,46].…”

Section: Mechanical and Tribological Propertiesmentioning

confidence: 99%

“…One of the prospective avenues of surface engineering is the deposition of hard, wear-, and oxidation-resistant transitional-metal based coatings for high-performance metal machining instruments by arc-evaporation and magnetron sputtering of composite targets [1][2][3][4][5]. Additionally, such coatings can be employed for heavy-duty friction pairs, high-temperature sensors, and resistive elements, critical parts for the aerospace industry.…”

Section: Introductionmentioning

confidence: 99%

Structure, Oxidation Resistance, Mechanical, and Tribological Properties of N- and C-Doped Ta-Zr-Si-B Hard Protective Coatings Obtained by Reactive D.C. Magnetron Sputtering of TaZrSiB Ceramic Cathode

Сытченко

Vorotilo

et al. 2020

Coatings

Self Cite

Coatings in the Ta-Zr-Si-B-C-N system were produced by magnetron sputtering of a TaSi2-Ta3B4-(Ta,Zr)B2 ceramic target in the Ar medium and Ar-N2 and Ar-C2H4 gas mixtures. The structure and composition of coatings were studied using scanning electron microscopy, glow discharge optical emission spectroscopy, energy-dispersion spectroscopy, and X-ray diffraction. Mechanical and tribological properties of coatings were determined using nanoindentation and pin-on-disk tests using 100Cr6 and Al2O3 balls. The oxidation resistance of coatings was evaluated by microscopy and X-ray diffraction after annealing in air at temperatures up to 1200 °C. The reactively-deposited coatings containing from 30% to 40% nitrogen or carbon have the highest hardness up to 29 GPa and elastic recovery up to 78%. Additionally, coatings with a high carbon content demonstrated a low coefficient of friction of 0.2 and no visible signs of wear when tested against 100Cr6 ball. All coatings except for the non-reactive ones can resist oxidation up to a temperature of 1200 °C thanks to the formation of a protective film based on Ta2O5 and SiO2 on their surface. Coatings deposited in Ar-N2 and Ar-C2H4 demonstrated superior resistance to thermal cycling in conditions 20-T−20 °C (where T = 200–1000 °C). The present article compares the structure and properties of reactive and “standard-inert atmosphere” deposited coatings to develop recommendations for optimizing the composition.

“…Max hardness (50 GPa) for nc-TiN/a-BN and nc-TiN/a-BN/a-TiB 2 coatings was achieved when TiN grains (25-30 and ≤10 nm, correspondingly) were separated by near-monoatomic layers of a-BN [31]. Doping of CrN by boron produces two types of nanocomposite structures: nc-CrN/a-BN [28,32] and nc-CrB2/a-BN [33]. Seventeen to 43 GPa hardness was reported for Cr-B-N coatings [34][35][36][37][38][39].…”

Section: Introductionmentioning

confidence: 99%

Effect of Boron and Oxygen on the Structure and Properties of Protective Decorative Cr–Al–Ti–N Coatings Deposited by Closed Field Unbalanced Magnetron Sputtering (CFUBMS)

Amankeldina

Sheveyko

et al. 2019

Applied Sciences

Self Cite

Boron and oxygen-doped Cr–Al–Ti–N coatings were deposited by closed field unbalanced magnetron sputtering (CFUBMS) of TiB target manufactured by self-propagating high-temperature synthesis, and Ti, Cr, and Al targets. To evaluate the influence of doping elements, as-deposited coatings were studied by glow discharge optical emission spectroscopy (GDOES), SEM, XRD, and optical profilometry. Mechanical properties were measured by nanoindentation and tribological, abrasive and electrochemical testing. The introduction of boron suppresses columnar growth and leads to structural refinement and a decrease of coating’s surface roughness. The addition of 2.3 at.% boron results in the highest mechanical properties: hardness H = 15 GPa, stable friction coefficient f = 0.65, and specific wear Vw = 7.5 × 10−6 mm3N−1m−1. To make the coating more visually appealing, oxygen was introduced in the chamber near the end of the deposition cycle. Upper Cr–Al–Ti–B–O–N layers were studied in terms of their composition and coloration, and the developed two-layer decorative coatings were deposited on cast metallic art pieces.