Titanium-cenosphere syntactic foam made through powder metallurgy route

Attempts have been made to use cenosphere as space holder to make Ti-cenosphere syntactic foam through powder metallurgy route. The cold compaction pressure was varied between 75 and 125 MPa in order to examine its effect on density, cenosphere crushing and strength of Ti-cenosphere foam. The cold compacted pallets were sintered at a temperature of 1100 °C for 2 h. Microstructural characteristics, density vis-a-vis porosity, compressive deformation behaviour and modulus of elasticity of the sintered samples were examined. It was noted that the porosity varies in the range of 51–70% depending on the pressure applied during cold compaction. A numerical model has been proposed to correlate density of foam with the extent of cenosphere crushing, density of cenosphere and density of titanium. The yield strength and modulus of elasticity of sintered foam samples are found to be a strong function of relative density.

► Cenospheres, a by-product from thermal power plant, has been used as space holder. ► To minimize crushing of cenosphere, controlled pressure has been applied. ► Modulus and strength of Ti-cenosphere foam examined as a function of density. ► The foams so made have reasonably good strength and modulus, but quite brittle. ► Cenosphere being very cheap, the foam so made would be cost competitive.