Effect of the microstructure on the cutting performance of superhard (Ti, Si, Al)N nanocomposite films

• Main Author: Fernandes, C.
• Publication Date: 2008
• Other Authors: Carvalho, S., Rebouta, L., Vaz, F., Denannot, M. F., Pacaud, J., Rivière, J. P., Cavaleiro, A.
• Format: Article
• Language: eng
• Source: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Download full: https://hdl.handle.net/1822/27576
• topic: (Ti,Si,Al)N; Microstructure; HRTEM; XRD; Science & Technology

A d.c. reactive magnetron sputtering technique was used to deposit (Ti,Si,Al)N coatings onto WC–Co cutting tools. The microstructure of the coatings was analysed using X-ray diffraction (XRD) and highresolution transmission electron microscopy (HRTEM) measurement. Before the cutting experiments, the XRD results revealed a structure indexed to an fcc TiN. The results obtained by the XRD tests, with detector variation in asymmetric mode (rocking curves) showed a decrease in the quality of the fiber texture in the (111) grains with the change on deposition chamber geometry (two magnetrons in place of four magnetrons). Cross-sectional HRTEM images of the (Ti,Al)N sample showed grains with a diameter between 16 and 30 nm, while for the (Ti,Si,Al)N samples grains with a diameter between 6 and 10 nm were observed. Furthermore, through the visualization of bright field images it was possible to discern a columnar structure. For samples prepared at high deposition rates (2 mm/h), HRTEM micrographs revealed the formation of the multilayer stacking of (Ti,Si)N/(Ti,Al)N.