PRODUCING HIGH-TEMPERATURE TITANIUM ALLOYS OF TI-AL-ZR-SI-MO-NB-SN SYSTEM BY ELECTRON BEAM MELTING.

A complex of research work was performed on the base of eBm technology to produce high-strength complex titanium alloys of Ti-Al-Zr-Si-Mo-Nb-Sn system with silicon content, higher than the thermodynamically stable value in the solid solution. alloys of this system are promising for creation of a new class of materials with a high level of heat-resistant characteristics. It is shown that EBM allows producing ingots of high-temperature titanium alloys of Ti-Al-Zr-Si-Mo-Nb-Sn system, which are characterized by sufficient chemical homogeneity and absence of casting defects. It is found that tin presence lowers silicon solubility in the test alloys and intensifies silicide release. Here the structure is also refined. It is found that additional alloying elements influence silicon solubility in titanium, forming complex silicides of (Zr, Ti)5si (ti, Zr)3si type in the test alloys. It is shown that the microstructure of the test cast alloys consists of platelike a-phase packets within primary ß-grains, having different crystallographic orientation. [ABSTRACT FROM AUTHOR]