The aim of this study was the fabrication and characterization of the novel hybrid composite from the Al2O3/Cu/Ni system. The research included the production of composite specimens by uniaxial pressing and their further sintering. The influence of the ceramic and metallic powders and their sintering temperature on the microstructure of composites was investigated. The firing process was conducted in reducing the atmosphere at three different temperatures, selected on the basis of the copper‐nickel phase diagram: 1100 °C, 1260 °C, 1400 °C. Reference samples of Al2O3/Cu were also produced in the same way for comparative purposes. The addition of the third component, which together with copper will form a Ni−Cu solid solution, was intended to improve the wettability of ceramic matrix through a liquid metallic phase, and thus to reduce the phenomenon of the liquid metal flow on samples surface during sintering. However, it had an impact on physical and mechanical properties.

The aim of this paper was to establish the general suitability of the centrifugal slip casting technique for fabrication of graded material from the Al 2 O 3-Cu-Ni system. The present investigation is a preliminary one and the obtained results may be regarded as a point for acquiring the new knowledge in the ternary ceramic metal system fabricated using centrifugal slip casting. The rheological study provided the evidence that the suspension used to fabricate composites is a non-Newtonian slurry. Moreover, the results demonstrated that the prepared slurry is stable over time. The obtained composites has a hollow cylindrical shape with relative density of > 95%. The XRD study results revealed three phases: Al 2 O 3 , Ni, and CuNi. The microscopic investigations revealed a nonhomogeneous distribution of the metallic phase in the composite. It has been shown that the content of the metallic phase decreased with the increased distance from the outside to the inner edge of the ceramic-metal composite. The study results allow to conclude that the interface between the phases is more continuous when sintering was carried out in a solid phase. However, it was found that when sintering was carried out in a liquid phase separated metal particles with spherical phase are formed.

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The article presents an assessment of the possibilities of producing viscoelastic open cell polyurethane (PUR) foams produced with a natural filler in the form of mint leaves. PUR foams containing from 10 to 30 wt % of mint were produced. Chemical structure, thermal and mechanical properties of the foams were assessed. It was found that the filler containing 7 wt % of water caused significant changes in the foam characteristics. In composite foams, the content of urea and hydrogen bonds increased with higher mint contents. The hardness and comfort factor of composite foams also increased. The introduction of a filler containing a significant amount of water caused a change in the porosity and wall thickness of composite foams resulting in a significant increase in their permanent deformations.

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