Author/Authors :
Dadkhah Tehrani, M. Hassan Malek-Ashtar University of Technology, Isfahan, Iran , Jafari Tadi, A Malek-Ashtar University of Technology, Isfahan, Iran , Yaghoubi Askarabad, Y Islamic Azad University, Isfahan, Iran , Karimian, M Islamic Azad University, Isfahan, Iran , Amini, K Department of Mechanical Engineering - Tiran Branch Islamic Azad University, Isfahan, Iran , Dadkhah Tehrani, M. Hossein Malek-Ashtar University of Technology, Isfahan
Abstract :
In the present work, structural characteristics and tribological properties of Ti-Al-Cr-(Si)-C-N nanocomposite films coated on SPK 1.2080 tool steel by PVD technique have been investigated. The PVD coating process was carried out using Ti (Si) Al and CrAl cathodes at 150 A current, 40 V bias and (Ar)0.1(CH4)0.45(N2)0.45 gas mixture for 50 min. Evaluations were conducted by OM, FESEM, AFM, XRD, nano and micro-indenters, and pin-on-disk tribometer. The uniform films with an about 2.5 μm thickness and 11.7 and 9.5 nm crystallite size values were respectively formed on the Ti-Al-Cr-C-N and Ti-Al-Cr-(Si)-C-N coated specimens. Surface hardness of the Ti-Al-Cr-C-N and Ti-Al-Cr-Si-C-N-coated samples was respectively obtained 8.7 and 10.8 GPa compared to 2.16 GPa for the un-coated substrate. Roughness (RMS), reduced modulus (E) and H/E ratio related to the Si-incorporated film were respectively determined 4.6 nm, 477 GPa and 0.081 while the mentioned values were 9.7 nm, 364 GPa and 0.075 for the Si-emptied film. Tribological properties were significantly enhanced by both films particularly by the Si-incorporated kind.
Keywords :
Tool steel , Ti-Al-Cr-(Si)-C-N , Microstructure , Tribological behavior
