Bending strength, thermal and electric conductivity and microstructure
examinations of Cu based composite materials reinforced with
Saffil alumina fibres are presented. Materials were produced by squeeze
casting method applying the designed device and specially
elaborated production parameters. Applying infiltration pressure of 90MPa and
suitable temperature parameters provided manufacturing of copper based
composite materials strengthened with Saffil alumina fibres
characterized by the low rest porosity and good fibre-matrix interface.
Three point bending tests at temperatures of 25, 100 and 300ºC were
performed on specimens reinforced with 10, 15 and 20% of Saffil fibres.
Introduced reinforcement effected on the relatively high bending
strengths at elevated temperatures. In relation to unreinforced Cu
casting strength of composite material Cu – 15vol.% Saffil fibres
increase by about 25%, whereas at the highest applied test temperature
of 300o C the improvement was almost 100%. Fibres by strengthening of
the copper matrix and by transferring loads from the matrix reduce its
plastic deformation and hinder the micro-crack developed during bending
tests. Decreasing of thermal and electrical conductivity of Cu after
incorporating fibres in the matrix are relatively small and these
properties can be acceptable for electric and thermal applications.