Thermal crack network on CVD TiCN/α-Al2O3 coated cemented carbide cutting tools

Recent Advances in Turning Processes Using Coated Tools—A Comprehensive Review

“…As mentioned previously, understanding cutting tool behavior is the key to correctly optimizing a machining process. There are many studies on coatings' behavior while cutting, for example, in the study presented by Gassner et al [57], the thermal crack network on CVD TiCN/Al₂O₃-coated The reason for this hardness increase was attributed to the large number of interfaces between layers, characteristic of nanolayered coatings. In Figure 9, the structure of a CrN/TiAlN nanolayered coating deposited on steel is shown [14].…”

“…As mentioned previously, understanding cutting tool behavior is the key to correctly optimizing a machining process. There are many studies on coatings' behavior while cutting, for example, in the study presented by Gassner et al [57], the thermal crack network on CVD TiCN/Al₂O₃-coated The structure shown in Figure 9, characteristic of nanolayered coatings, confers the coatings a very high crack propagation resistance, as the cracks tend to not propagate as deep as in a monolayered coating, thus risking damage to the substrate. These coatings are very similar to the multilayered coatings, the main difference being the thickness of each layer and that the hardness value for a nanolayered coating is not equal to the average hardness of its constituents-however, this is the case for regular multilayered coatings [14].…”

“…As mentioned previously, understanding cutting tool behavior is the key to correctly optimizing a machining process. There are many studies on coatings' behavior while cutting, for example, in the study presented by Gassner et al [57], the thermal crack network on CVD TiCN/Al 2 O 3 -coated cemented carbide cutting tools is analyzed. The theme of coating tools and coating performance is heavily researched, comparing coating methods to achieve overall better machining results, or even finding an eco-friendlier alternative to machining certain materials.…”

“…Also due to temperature, thermal cracking may occur on the coating. Another study regarding thermal cracking of CVD TiCN/Al 2 O 3 -coated cemented carbides [57] analyzes various methods to close the cracks that occur due to excessive cutting temperature, such as wet blasting or filling the cracks with TiO 2 . This wear mechanism can be observed in Figure 14, taken from the same work.…”

“…(a) SEM image of rake face of a coated CVD insert after face turning (b) highlighted section of the rake face. Reproduced from[57], with permission from Elsevier, 2019.…”