Engineered TiO sub(2) and SiO sub(2)-TiO sub(2) films on silica-coated glass for increased thin film durability under abrasive conditions

Thin films durability is critical to retain its performance in real life applications. For automotive glass, further factors such as haze appearance developed under abrasive conditions become relevant to ensure the driver's visibility. Macroscopic abrasion resistance tests of TiO sub(2)/SiO sub(2) and SiO sub(2)-TiO sub(2)/SiO sub(2) thin films on soda-lime silica (SLS) glass were performed according to an American standard for safety grazing. The purpose of this, was to increase the top active film durability in a bilayer system by understanding how film thickness and top film composition influence abrasion performance. In order to achieve this understanding, three approaches were considered: (a) determination of the influence of TiO sub(2) top film thickness, (b) replacement of the TiO sub(2) top film by SiO sub(2)-TiO sub(2) films, and (c) determination of the influence of SiO sub(2)-TiO sub(2) film thickness. Results showed that thinner top TiO sub(2) film thickness leads to SiO sub(2)/TiO sub(2) bilayers with lower haze value and improved abrasion resistance. It was also found that SiO sub(2) addition to TiO sub(2) top film composition promotes the thin film adhesion and sample durability against abrasive wear. Friction coefficient and micro-hardness measurements support the abrasion results. Factors contributing to the improvement of the lifetime performance of TiO sub(2) and SiO sub(2)-TiO sub(2) thin films were identified.