Wear of non-metal slides under very high load

The tests described in the article are related to the project of a high-altitude scientific rocket, which is expected to be built in the Institute of Aviation. The unguided rocket will be launched from a platform with a relatively long start beam and will be supported by slides at the start. Because of the relatively high rocket mass and nearly horizontal start needed for initial rocket tests, its slides will be under extremely high load defined as a combination of pressure and sliding velocity. In addition to the mechanical load, the slides will be also loaded thermally because of the friction in a pair: slide-guide rail (made of hard-anodized aluminium alloy). This leads to rapid wear of the slides. The aim of the tests was to establish what the friction coefficient between the slide and the guide rail is (as function of mechanical load) and how big slide-wear in a single work cycle (simulation of a single rocket launch) is. The tests were performed for few material samples: two modern plastics used in so-called “linear systems” (offered by a firm, which is one of the leaders on this market), samples made of well-known and widely used materials like cotton-phenolic textolite and well-known samples of material called Teflon (PTFE – polytetrafluoroethylene) with 15% addition of graphite. Results show that the temperature resistant plastic used in general linear systems at our condition are on the verge of wear according to our model. Textolite and Teflon with graphite addition have better characteristics of wear. They can be safely used as material of slides.