Reactive sintering of molybdenum disilicide by spark plasma sintering from mechanically activated powder mixtures: Processing parameters and properties

Dense molybdenum disilicide with a nano-organized microstructure was synthesized by mechanical activation, by producing nanostructured agglomerates of a 1:2 mixture of Mo and Si, followed by the synthesis/consolidation in one step using SPS technology. In order to synthesize a dense molybdenum disilicide with a perfectly controlled microstructure, an investigation of the influence of Spark Plasma Sintering processing parameters (temperature, heating rate, mechanical pressure and holding time) on the chemical composition and the microstructure characteristics has been performed. The present work shows also that the so-obtained materials present better oxidation resistance in comparison to a dense microstructured MoSi2, due to the silica scale formation under high-temperature oxidizing atmosphere. The most interesting results are obtained at 'low' temperature (673-873 K)