Thin film quality of sol–gel SiO2 coatings prepared on Ti6Al4V depending on their composition and titanium substrate preparation

The study examined the effect of chemical modification of the surface of the Ti6Al4V substrate in the form of etching with a 5 M NaOH base and etching with a 30% HNO 3 + 3% HF acid mixture on sol–gel coatings quality. Two SiO 2 coatings with different compositions were selected for testing: I SOM coating with a methyl group, –CH 3 , and II BOM coating with a methyl group -CH 3 , epoxy group, –COC–, and amine group, –NH 2 . The quality of the coatings was examined in terms of their morphology, thickness, and destruction, as a result of mechanical factors: cross section test, static tensile test, friction test, and wear tear. The influence of chemical etching on functionalization of the titanium alloy substrate significantly influencing the applied properties of the sol–gel coating was demonstrated. The findings provide a foundation for future research on quality of sol–gel functionalized coatings on Ti6Al4V substrate.