Surface Morphology and Strength Behaviour of Vitreous Films SiO <sub>2</sub>-P <sub>2</sub>O <sub>5</sub>-Nd <sub>2</sub>O <sub>3</sub>
The morphology and microstructure of silicophosphate films, undoped and doped by neodymium, were considered in the work. Strength characteristics (Young modulus and hardness) of the SiO <sub>2</sub>-P <sub>2</sub>O <sub>5</sub>-Nd <sub>2</sub>O <sub>3</sub> and SiO <sub>2</sub>-P <sub>2</sub>O <sub>5</sub> films under P <sub>max</sub> = 10 mN were also studied. In addition, the investigation of the soda-lime glass (SLG) substrate and, in general, of the composite structures SiO <sub>2</sub>-P <sub>2</sub>O <sub>5</sub>-Nd <sub>2</sub>O <sub>3</sub>/SLG and SiO <sub>2</sub>-P <sub>2</sub>O <sub>5</sub>/SLG (Р <sub>max</sub> = 10, 100 and 900 mN) was carried out. A specific microstructure, composed of the basic film on which structural units of small dimensions, about 0.1-0.2 μm, quasi-uniformly distributed, together with roundly structural units from several to tens micrometers, was detected on the SiO <sub>2</sub>-P <sub>2</sub>O <sub>5</sub>-Nd <sub>2</sub>O <sub>3</sub> and SiO <sub>2</sub>-P <sub>2</sub>O <sub>5</sub> film surfaces. The film surface morphology and microstructure exhibited a high time-stability as a result of the long-term rest (3 years). It is determined that both the films and composite structures possess the strength properties of high quality.