The study examined the tribological characteristics of a ball-on-disc type sliding friction joint operating in air and in a vacuum under conditions of technically dry friction. The test elements included discs made of 100Cr6 steel without coating, with an anti-wear TiN coating, and a low-friction MoS2/Ti coating, and bearing balls made of 100Cr6 steel and Al2O3 as counter-samples. The tribological properties of the studied friction joint were evaluated based on changes in the coefficient of friction, the intensity of linear wear, the ball wear diameter, and the appearance of worn surfaces. The environment of the friction joint was found to have a significant effect on the tribological characteristics of the studied friction pairs.