Producing of composite materials with aluminium alloy matrix containing solid lubricants

摘要

The paper presents the basics information about manufacturing and selected properties of composite with aluminum alloy matrix containing glassy carbon as a solid lubricant. The so far used method based on mixing the prepared glassy carbon particles with a liquid metal matrix, has been compared with a new method elaborated by the authors of the article. With this novel method carbon is introduced into a composite with the application of liquid carbon precursor and porous ceramic foams. It is then followed by precursor pyrolysis where, as the result, glassy carbon is obtained. Ceramic foams help liquid precursor penetrate the ceramic spheroid pores by forming a thin film of glassy carbon on their walls. The composite produced in such a way features uniform distribution of carbon within its entire volume which significantly improves tribological properties of the composite. Costly mixing procedure is not needed. Sliding friction coefficient of the new composite against cast iron (Iu = 0.06-0.28 at wearing in and 0,12 after wearing in) is much lower than in case of composite containing only ceramic foam as a reinforcing phase (pl = 0.25-0.32).