Incipient plasticity of CVD Al2O3/TiCN multilayer coatings during nanoindentation
| Reference number | |
| Coordinator | Lunds universitet - Institutionen för maskinteknologi - Lunds universitet |
| Funding from Vinnova | SEK 407 000 |
| Project duration | August 2019 - April 2022 |
| Status | Completed |
| Venture | Research infrastructure - utilisation and collaboration |
| Call | Industrial pilot projects for utilisation of neutron- and photon based techniques at large scale infrastructures - spring 2019 |
| End-of-project report | 2019-02590_SecoTools.pdf (pdf, 211 kB) |
Purpose and goal
The purpose of the project was to characterize the mechanical and structural change of CVD coatings under load. This by adapting a nano-indentation instrument to be used in beam experiments at synchrotron facilities. We have successfully achieved this goal as we were able to conduct this type of experiment at the NanoMAX synchrotron beamline at MAXIV laboratory where we performed in-situ characterization of the mechanical behaviour and structural evolution of thin CVD coating layers under several nanoindentation loads.
Expected results and effects
The results from time resolved synchrotron diffraction measurement with high spatial resolution (100 nm) enabled the evolution of elastic strains and related internal stresses in the individual coating layers to be measured with great accuracy. Such results will be utilized at Seco to systematically evaluate the role of the composition of coating material (microstructure, grain size, crystallographic orientation) and coating architecture (single, multilayer) on its mechanical response.
Planned approach and implementation
CVD coatings with different textures were deposited on cemented carbide substrates. The initial condition (microstructure, stress, thickness) was studied using laboratory XRD and EBSD. Lamellae were made from these samples using mechanical polishing and a focus beam (FIB). The lamellae were subjected to nanoindentation (force up to 0.3 N with a diamond wedge) while synchrotron diffraction data were collected at the same time at the NanoMAX beam line. From the analysis of the diffraction data, different maps showing changes in elastic strain/stress in the coating were calculated.