Consolidation of combustion-synthesized titanium diboride-based materials

Article abstract of DOI:10.1111/j.1151-2916.1995.tb08797.x

The quasi-static consolidation in uniaxial compression of combustion-synthesized TiB₂-based materials was investigated. Consolidation was carried out in insulated containers upon completion of the combustion reaction, while the porous reaction products were ductile. Since the consolidation is not an isothermal process, the temperature change during consolidation was monitored and recorded. The effect of the addition of metallic elements to the elemental powders was established, and it was found that nickel and chromium provide the best compact integrity. The partial densification is sufficient to show significant differences between the effects of metallic additives. A phenomenological (not based on the micromechanisms of densification) constitutive model was applied to the hot and porous reaction products incorporating the temperature dependence of flow stress. The activation energy for the temperature dependence of the flow stress is established and indicates that, in addition to diffusion-induced plastic deformation, other processes occur, such as fracturing of ligaments.