Effect of Ethanol on the Phase and Elemental Composition of Mechanically Activated Titaniumcarbon Powder Mixtures

Abstract

Using the method of hot compaction (HC) of mechanically activated powder mixtures of titanium and carbon (carbon black) in an ethanol medium, titanium-matrix composites with a carbide strengthening phase were obtained. To obtain a composite with different content of titanium carbide, the amount of carbon was varied within the range of 0–1 wt.%. The mechanically activated carbon-doped titanium powder mixtures, as well as the mechanically activated titanium powder subjected to HC (temperature of 900°C and holding time of 15 min) and additional annealing at different temperatures and holding times are studied by optical metallography, scanning electron microscopy, and X-ray diffraction and chemical analysis. According to the metallography and X-ray diffraction results, the TiC content in the HC composite has been found to be significantly higher than the estimated value. The reason is a destruction of ethanol molecules during mechanical activation resulting in the release of carbon and hydrogen. To obtain the targeted (no more than 10 vol.%) TiC content in the titanium matrix composite, it is necessary to establish a specific technological mode for the mechanical activation of the titanium powder.