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Note: UMS, unbalanced magnetron sputtering; MS, magnetron sputtering; IP, ion plating; SAD, steered-arc deposition; AD, arc deposition; RF-MS, radio frequency magnetron sputtering.

Source: Reprinted with permission from [175], G. M. Demyashev et al., in "Handbook of Organic-Inorganic Hybrid Materials and Nanocomposites" (H. S. Nalwa, Ed.), Vol. 2, Chap. 13. American Scientific Publishers, Stevenson Ranch, CA, 2003. © 2003, American Scientific Publishers.

Note: UMS, unbalanced magnetron sputtering; MS, magnetron sputtering; IP, ion plating; SAD, steered-arc deposition; AD, arc deposition; RF-MS, radio frequency magnetron sputtering.

Source: Reprinted with permission from [175], G. M. Demyashev et al., in "Handbook of Organic-Inorganic Hybrid Materials and Nanocomposites" (H. S. Nalwa, Ed.), Vol. 2, Chap. 13. American Scientific Publishers, Stevenson Ranch, CA, 2003. © 2003, American Scientific Publishers.

coatings possess relatively high compressive intrinsic stress, for example, VN/Ti^A^^^N (-8 GPa), CrN/NbN (-6.5 GPa), CrN/Ti%Al1-%N ' (-9.2 GPa), and ZrN/ TixM-xN (-10 GPa).

In a number of cases [455-457, 559], the nanolayered composites demonstrated comparatively low hardness, contrary to what was expected. For example, the TiN/CrN nanolayered composite coating deposited on the (WC-Co) cemented carbide with a bilayer repeat period of 1521 nm exhibited a maximum microhardness of only 30 GPa [455-457].

For the deposition of nanolayered composites, very complicated facilities with low efficiency should be used. For example, the coatings of TiN/VN and TiN/NbN were obtained using a computer-controlled shutter [377, 397]. For a typical growth rate of approximately 1 ¡xm/h, the required time for Ti/V target exposure for every nanolayer should be less than 1 s, which corresponds to a deposition thickness of less than 0.3 nm [377]. In the case of TiN/NbN nanocompos-ite coatings [397], the shutter shadowed the Ti/Nb targets for about 0.15 s. This technique should be supplied with a computer-controlled shutter [397] or a rotating substrate

Table 2. Summary of the achievable physicomechanical properties of superhard nanolayered composites.

Oxidation resistance (up to °C)

Table 2. Summary of the achievable physicomechanical properties of superhard nanolayered composites.

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