Ti-Si AND Ti-B-SYSTEMS AS THE BASE FOR NEW TITANIUM MATRIX COMPOSITES

摘要

Eutectic crystallization is one of the ways to produce so-called in-situ composites. Reinforcing phase is produced in a course of solidification at high temperature that results in its high thermodynamically stability at long term heating in a range of temperatures up to 0.4 of melting temperature T_(melt). As to the composites based on titanium alloys of Ti-B and Ti-Si-systems with eutectics of 1 540 and 1 330°C melting temperatures correspondingly are of the most interest. According to [1] the volume part of reinforcing phase consists of 7.7 vol.% in the Ti-B-system and 31 vol.% in the Ti-Si-ones. The latest research showed that volume part of reinforcing phase in the Ti-B-system might be higher and consist of 14 vol.%. The data [1-3] show that alloys of the named systems are suitable candidates to produce new generation of heat resistant materials based on titanium. Additional enhancement of properties might be achieved with alloying them with Zr, Al, Sn, Ge, Ga etc. [4-7].