Influence of the Chemical Composition and Topography of the Ti6Al7Nb Surface Etched in Fluorine Plasma on Its Selected Properties

Herein, a new way of the surface modification of Ti6Al7Nb alloy in fluorine plasma is presented using the mask made of stainless steel and its influence on the selected properties, including chemical composition, topography, and tribological ones. Depending on the etching process parameters, different characteristics of the surfaces are obtained. The higher is the value of the negative bias, the less fluorine concentration on the etched surface and higher etching rates. Etching using the SF₆ gas shows bigger etching rates in comparison to the etching using the CF₄ gas. Chemical composition of the modified surfaces shows greater impact on tribological characteristics than topography parameters. The lowest wear rate is observed for the sample modified using the CF₄ gas.