Year: 2025
Type: article
Abstract: Nanoindentation-based fracture toughness measurements of three different materials based on copper oxide with a Berkovich indenter are fascinating topics in material science. The main purpose of this study was to calculate the fracture toughness in mode I (KIc) for three copper oxide coatings (Cu+CuO) deposited on a steel substrate by the DC magnetron sputtering method. The parameter KIc can be referred to as the critical load (Pcritical), where the cracking process is initiated uncontrollably. The basic mechanical parameters, such as the hardness and Young’s modulus of Cu+CuO coatings, were determined using a Berkovich nanoindenter operated with the continuous contact stiffness measurement (CSM) option. Structural observation was performed by scanning electron microscopy (Helios). Using the nanohardness tester from Anton Paar with a Berkovich diamond indenter with experimentally selected load allowed generation of visible and measurable cracks, which were necessary for KIc calculation. Crack lengths were measured by scanning electron microscopy (SEM Hitachi TM3000). The obtained results indicated that the values of hardness and Young’s modulus of Cu+CuO coatings decreased as the power of the magnetron source and the fracture toughness coefficient increased. In the case of the presented study, the Laugier model was chosen for KIc determination.
Source: Materials
DOI: 10.3390/ma18040885
Language: English
Subfield: Mechanics of Materials
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,137
Funder: Sieć Badawczą Łukasiewicz
OpenAlex ID: W4407702308