Mechanical properties and oxidation resistance of sputtered Cr–W–N coatings

Impact of Tungsten Incorporation on the Tribomechanical Behavior of AlCrWxSiN Films at Room and Elevated Temperature

“…With increased tungsten contents there was a substantial growth of the peak intensities at 2θ = 37.6°, 43.7°, 63.4°, and 76.1°, i.e., a more textured crystallite structure was developed due to the distinct (111), ( 200), (202), and (311) orientations of the fcc crystals. Similar results are reported in numerous studies, which concern the texture alteration from (111) to a (200) orientation with increasing W contents in sputtered Cr1-xWxNy films [4][5][6]. However, since the cubic CrN, W2N, and WN lattices are roughly equal in their lattice parameters (CrN = 0.4148 nm, WN = 0.4130 nm, and β-W2N = 0.4126 nm) [30], superpositions of the reflexes at 2θ = 37.6°, 43.7°, 63.4°, and 76.1° occurred.…”

“…Table 1), i.e., when the tungsten content exceeded the chromium content and more (200) orientations were formed (Figure 2). Similar to the results of Chang et al, who analyzed CrWN films [6], a pronounced (200) orientation of the fcc crystal can account for hardness values >20 GPa. As is known from the literature, the tungsten incorporation in CrWN evokes a phase strengthening effect that is based on more covalent bondings leading to the formation of a solid solution [2,19,33].…”

“…Chang et al systematically varied the Cr and W contents in a CrWN system and showed that when exposing the substrates alternately to Cr and W targets with different powers, a stacking of CrN and W 2 N nanolayers occurs. Thus, this phenomenon was described as a mixed CrN-W 2 N phase with a chemical composition that is dependent on the individual target powers [6]. Similarly, Figure 2 indicates that the intensity and width of the pronounced (111) reflex increased with increasing W HiPIMS powers, suggesting the formation of more tungsten nitrides accompanied by decreased grain sizes.…”

“…Hones et al showed that Cr 1−x W x N films with 0.1 ≤ x ≤ 0.8 exhibited a significantly higher hardness (24-29 GPa) when compared to binary CrN (13 GPa) [4]. With regard to the crystallographic properties, the crystal orientation changes from (111) to (200) with a higher W concentration, while maintaining an fcc structure [4][5][6]. Increasing tungsten concentrations further changes the film morphology from columnar to a fine-grained structure, resulting in a linear increase of the compressive stresses [4].…”

Bonding Characteristics and Chemical Inertness of Zr–Si–N Coatings with a High Si Content in Glass Molding

“…Therefore, the requirements of protective coatings are high hardness, smooth surface morphology, high thermal stability, adequate adhesion, long cyclability, and chemical inertness. Following the successful utilization of noble metal alloys [4][5][6][7][8][9][10][11] and carbon films [12,13], transition metal nitride films [14][15][16][17][18][19][20][21][22][23], which offer cost reduction and process control benefits, have become candidates for protective coatings. The oxidation resistance levels of some transition metal nitrides have been improved by the introduction of Si; in particular, improvements to Ti-Si-N [24][25][26] and Zr-Si-N [27][28][29] coatings have been reported.…”