Fracture toughness of free-standing nanocrystalline copper–chromium composite thin films

Nanostructured copper and copper oxide thin films fabricated by hydrothermal treatment of copper hydroxide nitrate

“…To this end, a variety of organic and inorganic materials such as polymers, pure and doped metal oxides/hydroxides and carbon materials have been successfully coated onto different substrates for specific purposes. Accordingly, copper oxide (CuO) (a p-type semiconductor with band gap energy of 1.4 eV in its bulk form) is a good candidate to be fabricated as a thin film due to its potential applications as gas sensors, batteries, solar cells as well as photocatalysts [3][4][5]8,9]. On the other hand, copper (the reductive product of copper oxide) is one of the most important metals in modern technologies [7,10].…”

Analytical estimation of fracture toughness for circumferential cracks in thin hard films on ductile substrates

“…To learn how cracks grow through thin coatings in indentation test, many numerical simulations were done to calculate the energy release rate G, and the stress intensity factor K, for a crack in the thin films . For example, Abdul‐Baqi and Giessen, Sriram et al, Vanimisetti et al, Pachler et al, Steffensen and Jensen, and Hyung Kim et al studied toughness and tress numerically in indentation tests that applied to thin coatings on a soft substrate . Also, to calculate fracture toughness (Γ F ) with different tests including indentation, bending, and microstretching, different methods were proposed, which Zhang has collected and introduced many of these methods in his research.…”

“…6 For example, Abdul-Baqi and Giessen, Sriram et al, Vanimisetti et al, Pachler et al, Steffensen and Jensen, and Hyung Kim et al studied toughness and tress numerically in indentation tests that applied to thin coatings on a soft substrate. [6][7][8][9][10][11] Also, to calculate fracture toughness (Γ F ) with different tests including indentation, bending, and microstretching, different methods were proposed, which Zhang has collected and introduced many of these methods in his research. In most of the proposed methods, it was assumed that the crack was starting from the coating and propagate to the interface.…”