Titanium-boride eutectic materials: Structure of titanium-rich Ti-Ge-B alloys and phase equilibria at crystallization temperatures

Abstract

Phase equilibria in the Ti-TiB 2 -Ti 5 Ge 3 region of the Ti-Ge-B system are experimentally investigated at melting/solidification temperatures using x-ray diffraction, metallography, EMPA, and differential thermal analysis. The phase diagram is presented as projections of solidus and liquidus surfaces and a vertical section at 7.5 at.% B.

Five decades of research on the development of eutectic as engineering materials

“…The alloys containing 7.5 at % B and 17 at.% Nb form eutectic that can be of interest [138]. Replacing Nb with Ge also yields a three-phase eutectic (Ti 0.91 Ge 0.09 ) + Ti 6 Ge 2 B + (Ti 5 Ge 3 ) in Ti-Ge-B system [139]. In Ti-Si-B ternary system, in addition to binary Ti SS -Ti 3 Si eutectic, a three-phase eutectic Tiss + Ti 6 Si 2 B + Ti 5 Si 3 (eutectic) is present [140].…”

Effect of doping with p-elements (Al, Si, Ge, Sn) and zirconium on the structure and properties of titanium-boride eutectic alloys

“…Germanium concentrates in the metal matrix when its content is to 4 at.% and partitions among the titanium, Ti 6 Ge 2 B, and Ti 5 Ge 3 phases at higher contents. The greater the germanium content, the lower the melting temperature and the temperature of β + TiB ↔ α solid-phase transition in the alloys [35]. The microhardness of both the eutectic component and the metal matrix increases with germanium content (Fig.…”

“…For this reason, a scientifically sound selection of a doping agent is hardly possible. The previous papers focused on examining the phase equilibria and constructing the phase diagrams in titanium corners of the following ternary systems: Ti-Al-B [32], Ti-Si-B [12,33], Ti-Ge-B [34,35], and Ti-Sn-B [36] ( Table 2). The objective of this paper is to analyze how doping with p-elements (Al, Si, Ge, Sn) and zirconium influences the structure and mechanical properties (hardness from room temperature to 900°C, strength, and plasticity) of alloys based on the two-phase titanium-boride eutectic.…”

Elastic and electronic properties of the Ti5X3 (X=Si, Ge, Sn, Pb) compounds from first-principles calculations

“…Therefore, structural properties [14][15][16][17], point defects and chemical potentials [18,19], electronic densities of states [13,17] and enthalpy of formation [18][19][20][21] of these compounds have been explored. Recently, extensive investigations of the Ti 5 X 3 (X¼Si, Ge, Sn, Pb) compounds have been carried out owing to intriguing properties at elevated temperature [18,19,[22][23][24]. However, to the best of our knowledge, there are quite few theoretical and experimental reports of the mechanical and electronic properties for Ti 5 X 3 (X¼Si, Ge, Sn, Pb) [2,3].…”