Self-propagating high-temperature
synthesis in Ti-W-C system
synthesis in Ti-W-C system
(1. College of Materials Science and Engineering,
Fuzhou University, Fuzhou 350002, P.R.China；
2. Department of Materials Science and Engineering,
Central South University,Changsha 410083, P.R.China；
3. Department of Chemistry, Zhejiang University, Hangzhou 310027, P.R.China)
Fuzhou University, Fuzhou 350002, P.R.China；
2. Department of Materials Science and Engineering,
Central South University,Changsha 410083, P.R.China；
3. Department of Chemistry, Zhejiang University, Hangzhou 310027, P.R.China)
Abstract: The effects of W content and preheat temperature on combustion temperature, combustion velocity and product components of self-propagating high-temperature synthesis(SHS) in Ti-W-C system were investigated. The results show that with decreasing W content and increasing preheat temperature, the combustion temperature and combustion velocity increases, the SHS reaction becomes complete and the particle size of product increases. There exist two combustion mechanisms. When Ti powder in combustion front was molten by high combustion temperature, SHS product was formed by melt-solution-precipitation mechanism. When the combustion temperature was not high enough to make Ti powder melt in combustion front, the product was formed through diffusion-solution-in-solid-state.
Key words: self-propagating high-temperature synthesis (SHS); Ti-W-C system; combustion mechanism