Investigation of nanocrystal-(Ti1−xAlx)Ny/amorphous-Si3N4 nanolaminate films

Nanocrystal-(Ti1−xAlx)Ny/amorphous-Si3N4 nanolaminate films were deposited periodically via reactive magnetron sputtering technique. The effects of the thickness of multilayer period on the microstructure and mechanical properties were investigated by X-ray diffraction, scanning and transmission electron microscopies, nanoindentation and scratching adhesion testing. Results indicate that the nanolaminate structure is uniform and good flatness interfaces under different multilayer periods. The nanolaminate films exhibited a maximum hardness when the multilayer structure had a period of λ=25 nm and were harder than monolayer (Ti1−xAlx)Ny or Si3N4 films of the same thickness. The critical scratching load of the nanolaminates was higher than that of monolayer specimens with the same thickness. The mechanisms of fracture and toughening of nanolaminate films are also discussed.