Microstructural and Mechanical Properties of CrTiAlN Nanocomposite Thin Films Synthesized by Closed Field Unbalanced Magnetron Sputtering

Quaternary CrTiAlN nanocomposite thin films were synthesized by closed field unbalanced magnetron sputtering (CFUBMS) at various N-2 partial pressures, and their properties were evaluated. The preferred orientations of the CrTiAlN nanocomposite films were in the CrN (111) and CrN (200) directions. The black spots in the CrTiAlN nanocomposite films were proven by using a fast-Fourier transform (FFT) method to be a nanocomposite having in the [113] direction. The hardness of the CrTiAlN nanocomposite films ranged from about 30 similar to 39 GPa, with the highest hardness corresponding to a grain size of about 2.9 nm. The resistance to plastic deformation and the fracture toughness depended on the hardness and the grain size. The critical grain size needed to maximize the hardness, d(c), was also determined.