Structural and phase transformations in titanium alloys induced by ferrosilicon alloying

Abstract

The aim of this study was to investigate the structural and phase transformations in titanium alloys induced by ferrosilicon alloying and to enhance the physical and mechanical properties of titanium-based composite materials. These findings demonstrate that the use of FS65 ferroalloy as an alloying addition leads to active interaction with titanium hydride, resulting in the formation of a complex heterophase system. Using FS65 ferroalloy, boron carbide (B4C), and carbon (C) as alloying additions, the research identifies the optimal synthesis temperature and examines the resulting microstructures and phase formations. The optimal synthesis temperature was found to be 1250◦C. At this temperature, the phases TiC, TiSi, FeTi, and Ti3SiC2 were observed in the system 65 TiH2 – 30 FeSi – 5 C (wt.%), while TiC, Ti5Si4, Fe2Ti, and TiB2 were identified in the system 65 TiH2 – 30 FeSi – 5 B4C (wt.%). The addition of 5% B4C resulted in a finer microstructure with grain sizes ranging from 0.5 to 5 μm, compared to grain sizes of 5–10 μm with the addition of 5% C. The presence of B4C also promoted the formation of TiB2. The synthesized compacts, characterized by a fine-pored, spongy structure, are easily crushed, making them suitable for use as dispersed fillers in composite materials.