Properties of coatings used in biotribological systems

The properties of diamond-like carbon coatings (DLC) obtained via plasma-assisted chemical vapor deposition (PACVD) on the Ti13Nb13Zr alloy were evaluated. For this purpose, measurements of the thickness, the surface geometric structure, adhesion, as well as tribological tests of the tested coatings were performed. The thickness of the deposited coating was measured using the spherical grinding method. Surface geometry measurements before and after tribological tests were performed with a Leica DCM8 optical profilometer. A scratch test was performed to measure the adhesion of the coating. An indenter with a Rockwell geometry was used during the adhesion tests. The test offered the possibility of real-time recording of the coefficient of friction and acoustic emission. In addition, it was also possible to measure the geometrical parameters of a scratch and to carry out a microscopic analysis of a scratch during the coating damage. The test was carried out on an Anton Paar MCT3 instrument. The model tribological tests were carried out in rotary motion under technically dry friction conditions and friction conditions with lubrication with the Ringer’s solution and an artificial saliva solution. The tests were carried out using an Anton Paar TRB3 tribometer. The scratch test proved that the deposited layer was characterized by good adhesion. Based on the results of the tribological tests, it was found that the lower resistance to motion and wear was obtained for the DLC coatings on the Ti13Nb13Zr substrate. The results of the tests performed on the DLC coatings indicate the possibility of their application in biotribological systems.