Thermoanalytical studies of the ceramic-metal composites obtained by gel-centrifugal casting

Abstract

Composite material with a gradient concentration of the metallic phase was prepared by the novel gel-centrifugal casting method. This method combines the consolidation of powders by the centrifugal force with the reaction of radical polymerization of an organic monomer which simultaneously proceeds within the composite slurry. The combination of the centrifugal casting with gel-casting permits production of ceramic–metal composites, including materials with a gradient distribution of metallic particles in a ceramic matrix. Special attention was paid to the thermal analysis of the composite Al2O3–Ni green bodies and the binder used in the fabrication of the material. The experiments were performed on the simultaneous thermal analyzer coupled with the mass spectrometer. The measurements were carried out in air and the inert atmosphere (argon) what allowed to determine the effects characteristic for organic binder decomposition and type of gases released to the atmosphere during thermal treatment. The measurements allowed also to establish the sintering program of the green composite samples and evaluate whether harmful gases are released to the atmosphere. The thermal experiments were complemented with physical and structural measurements, including X-ray diffraction and scanning electron microscopy.