Studying the Formation of a Multilayer Functional Composite Material with a Titanium Nitride-Titanium-Base Gradient Structure

Composite materials based on aluminum alloy D16 and titanium alloy Ti-10Nb-3Mo with titanium and titanium nitride surface layers and on a multilayer composition consisting of alternating titanium and titanium nitride layers for biomedical and tribological purposes are synthesized by high vacuum magnetron sputtering with a direct current in inert and reactive media. The structure and phase composition are studied using SEM, AES, X-ray diffractometry, and scanning probe microscopy. The rate of formation of a surface layer of pure titanium on a substrate made of alloy D16 is 185 nm/min, and the kinetic rate of the synthesis of a surface layer of titanium is considerably slowed down in a reactive medium and is no more than 70 nm/min owing to nitrogen poisoning of the target. The intermediate layer formed as a result of the synthesis of a titanium layer on an aluminum alloy substrate has a thickness of about 600 nm, which is substantially greater than the thickness of the intermediate layer when titanium is deposited on a titanium alloy substrate. The nitrogen concentration observed during the formation of titanium nitride on a titanium sublayer is higher than that observed during the formation of the nitride on a substrate with the same deposition parameters. The intensity of the reflections of the TiN phase in the X-ray diffraction patterns are weakly expressed with all variants of the used Ar/N-2 ratios of working gases during sputtering. The presence of a titanium sublayer makes it possible to obtain a greater thickness of the titanium nitride layer and the surface layer saturated with nitrogen to a greater extent up to 38 wt % in comparison with the case of layer deposition without the sublayer.