125
Protection and Restoration
under deformation beyond the elastic limit, changing it from hard elastic to plastic
and avoiding brittle destruction of the material and improving its wear resistance
(Maitra, 2014).
Tominaga et al. (2012) report preparation of TiN thin films by sputtering in Ar
atmosphere, obtaining a crystalline structure even when the substrate temperature is
low. Direct sputtering of mixed TiN and AlN powders in Ar enabled production of
Ti–Al–N thin films of high mechanical strength. These films consist of crystalline
TiN and amorphous AlN when the proportion of two compounds is 50/50 (Tominaga
et al., 2012). It can serve as an example of the concept of second-generation Ti(X)
N coatings, where X denotes a metallic element introduced to the lattice of titanium
nitride to obtain more excellent resistance to wear and oxidation than of the firstgeneration TiN layer (Shen et al., 2021).
Research indicates that binary metal nitrides exhibit better characteristics than
conventional metals do (Pogrebnjak et al., 2019). The multilayer nitride coatings find
their applications in the aerospace industry, medicine, and manufacturing. Among
important applications of TiN-based coatings, Santecchia et al. (2015) point out
coating of cutting tools. Improved tribological properties promote reduced application of lubricating liquids, thus minimizing waste, providing a viable alternative
to wet machining in the form of dry machining. From a technological perspective,
high-speed machining requires improved heat and wear resistance due to local heat
generation as well as heat-insulating properties of a tool coating (Santecchia et al.,
2015). Typical properties of TiN coatings important for cutting tool applications can
be listed as follows (TiN Coatings, 2021):
• Thickness 2–4 µm
• Friction coefficient ca. 0.5 (depends on application and test conditions)
• Hardness (HV 0.05) 2200 (depends on application and test conditions)
• Working temperature max. 600°C
Pogrebnjak et al. (2019) emphasize that multilayer nitride coatings exhibit excellent
mechanical, optical, electronic, and magnetic properties, as well as improved durability and advantageous wear and corrosion resistance. They indicate specific combinations of functional characteristics of multilayer coatings related to the following:
1. Ability to provide final stresses of required sign and magnitude
2. Inhibition of heat flows due to frictional generation of heat during the cutting process
3. Limitation of interdiffusion processes between the coating and the substrate
After Pogrebnjak et al. (2019), some important examples of TiN-based multilayer
coatings can be provided.
Titanium nitride-based multilayer coatings may consist of two layers, e.g., TiN
and TiC, which contributes to a prolonged cutting tool lifetime compared to that
of a single-layer TiN coating. Further, combinations like TiN, TiC, and/or TiCN
with Al 2 O 3 are found advantageous, since a layer of titanium nitride provides a high
Protection and Restoration
under deformation beyond the elastic limit, changing it from hard elastic to plastic
and avoiding brittle destruction of the material and improving its wear resistance
(Maitra, 2014).
Tominaga et al. (2012) report preparation of TiN thin films by sputtering in Ar
atmosphere, obtaining a crystalline structure even when the substrate temperature is
low. Direct sputtering of mixed TiN and AlN powders in Ar enabled production of
Ti–Al–N thin films of high mechanical strength. These films consist of crystalline
TiN and amorphous AlN when the proportion of two compounds is 50/50 (Tominaga
et al., 2012). It can serve as an example of the concept of second-generation Ti(X)
N coatings, where X denotes a metallic element introduced to the lattice of titanium
nitride to obtain more excellent resistance to wear and oxidation than of the firstgeneration TiN layer (Shen et al., 2021).
Research indicates that binary metal nitrides exhibit better characteristics than
conventional metals do (Pogrebnjak et al., 2019). The multilayer nitride coatings find
their applications in the aerospace industry, medicine, and manufacturing. Among
important applications of TiN-based coatings, Santecchia et al. (2015) point out
coating of cutting tools. Improved tribological properties promote reduced application of lubricating liquids, thus minimizing waste, providing a viable alternative
to wet machining in the form of dry machining. From a technological perspective,
high-speed machining requires improved heat and wear resistance due to local heat
generation as well as heat-insulating properties of a tool coating (Santecchia et al.,
2015). Typical properties of TiN coatings important for cutting tool applications can
be listed as follows (TiN Coatings, 2021):
• Thickness 2–4 µm
• Friction coefficient ca. 0.5 (depends on application and test conditions)
• Hardness (HV 0.05) 2200 (depends on application and test conditions)
• Working temperature max. 600°C
Pogrebnjak et al. (2019) emphasize that multilayer nitride coatings exhibit excellent
mechanical, optical, electronic, and magnetic properties, as well as improved durability and advantageous wear and corrosion resistance. They indicate specific combinations of functional characteristics of multilayer coatings related to the following:
1. Ability to provide final stresses of required sign and magnitude
2. Inhibition of heat flows due to frictional generation of heat during the cutting process
3. Limitation of interdiffusion processes between the coating and the substrate
After Pogrebnjak et al. (2019), some important examples of TiN-based multilayer
coatings can be provided.
Titanium nitride-based multilayer coatings may consist of two layers, e.g., TiN
and TiC, which contributes to a prolonged cutting tool lifetime compared to that
of a single-layer TiN coating. Further, combinations like TiN, TiC, and/or TiCN
with Al 2 O 3 are found advantageous, since a layer of titanium nitride provides a high