Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1659577 | Surface and Coatings Technology | 2009 | 4 Pages |
TiAlNC coatings were prepared under various N2 flows by reactive dc magnetron sputtering. The composition, microstructure and hardness of TiAlNC coatings were investigated by energy dispersive spectroscopy, X-ray diffraction, scanning electron microscopy and micro Vicker tester. By increasing the N2 flow, the Al/Ti ratio and the nitrogen content of the coatings increased. It was found that hexagonal AlN phase precipitated under relatively high N2 flow (e.g. 8 sccm). The increase in the N2 flow also changed the preferred orientation of fcc Ti(Al)N(C) phase from random to [111], and then to [200]. The coating deposited at low N2 flow (e.g. 2 sccm) exhibited [111] preferred orientation with porous structure and relatively low hardness. However, when the N2 flow was relatively high (e.g. 8 sccm), the hcp AlN phase precipitation and N2-induced grain refinement resulted in a denser multiphase structure, which improved the hardness and toughness of the TiAlNC coating.