Titanium carbide particles as pre-solar grains

Abstract

Focusing on the growth of metal carbide particles and the formation of pre-solar grains, a new attempt has been made for titanium carbide (TiC) systems. Using the noble gas evaporation method, we succeeded in producing TiC core (50-nm) carbon mantle (2-nm) grains of the same core size as pre-solar grains. The infrared spectrum has broad absorption features at 9.5 and 12.5 µm. It was also found that these absorption peaks became weaker by an increase to 15 nm of carbon mantle layer. The determination method of the contact angle of carbon on the TiC grain has been developed using a high-resolution electron microscopic technique. The contact angles between TiC and carbon were 22. ◦ 8 ± 0. ◦ 7 and 24. ◦ 0 ± 0. ◦ 4 on the (111) and (100) TiC