Preparation And Tribological Properties Research Of C/B/Cu-Al Matrix Self-lubricating Materials

Graphite-Particle-reinforced aluminum matrix composite is a goodself-lubricating material compared. It is an environment friendly material withexcellent frictional performance and high specific strength, so it can be applied inmany fields in the future. However, due to the non-wetting of graphite and aluminium,it is very difficult to add graphite particles into molten aluminium. This is the coreissue of the preparation of aluminium-based self-lubricating materials reinforced withgraphite particles. During wear process, a graphite surface lubricating film formed.Due to weak binding force between graphite and aluminium, the lubricating film peelsoff easily. Without lubricating film, friction and wear performance decreases rapidly.In this paper, C/B/Cu materials was prepared by water (solvent) thermal,C/B/Cu-Al matrix self-lubricating composite uses C/B/Cu composite materials asself-lubricant was prepared by a casting technique. And through XRD, SEM,Mapping, TEM, microstructure observation, mechanical property test, friction andwear analysis to assessed the experiment results. According to research, C/B/Cucomposite materials improved the lubricating property of aluminum matrix compositeeffectively, overcame the upward demerits of Graphite-Particle-reinforced aluminummatrix composite. In addition, it has certain refinement effect to the aluminum alloymatrix, improve its mechanical properties.First, according to the difficulty of the poor wettability between the graphiteparticle and Al melt, C/B/Cu composite materials prepared by water (solvent) thermalwas studied. The influence of molar ratio of graphite, copper acetate and B2O3,reaction solvent type and reaction temperature was investigated importantly. Theoptimal processing parameters are determined. The high-resolution XPS spectra of thecomposite materials shows, the number of carbon and copper atom contained inthe material surface with ratio of2.37, and mass ratio was0.59.The optimal processing parameters are determined by systemic investigating thepreparation process of the C/B/Cu composite materials particle reinforced Al alloymatrix composite, and the composites in which the C/B/Cu powder is more anduniformly distributes is fabricated. Owing to wettability of C/B/Cu with Al and itsrefining effect, effectively improve the mechanical behavior of materials. Foundthrough microstructure observation, C/B/Cu distributed evenly in matrix, without agglomeration like graphite. After added3wt%C/B/Cu, tensile strength andelongation were increased10.8%and14.3%respectively, than added3wt%graphite.The tribological property is greatly improved with increasing of C/B/Cu content.The friction coefficient of the composites containing3wt%C/B/Cu is0.29(speed200r/min, load10kg, friction time2h). After added3wt%C/B/Cu, wearing rate weredecreased15.5%, than added3wt%graphite. The solid lubricating film composed ofFe oxide, C/B/Cu and a little Al oxide is formed on the friction surface by the electronmicroscopy analysis of the friction surface of the composites. Moreover, this solidlubricating film is more smooth，and the adhesive wear and abrasive wear are feweron the friction surface with increasing of content of C/B/Cu.