High-strength binary Ti–Fe bulk alloys with enhanced ductility

Abstract

The structure of hypoeutectic, hypereutectic, and eutectic Ti–Fe alloys produced in the shape of arc-melted ingots was found to consist of the ordered Pm-3m TiFe and disordered BCC Im3m β–Ti solid solution phase. The dimensions of the ingots were about 25–40 mm in diameter and 10–15 mm in height, and their structure was studied by x-ray diffractometry and scanning electron microscopy. The rectangular parallelepiped-shaped samples 2.5 × 2.5 × 5 mm in size cut from the central part of the ingots exhibit a high strength of about 2000 MPa, except for Ti60Fe40, and a certain ductility. The relatively low density of Ti (4.5 Mg/m3) implies high strength/density ratio for the studied alloys. These alloys are characterized by the low cost of the alloying element Fe and, compared to most of the high-strength non-equilibrium materials, do not require additional injection mold casting or rapid solidification procedures.

Ductile ultrafine-grained Ti-based alloys with high yield strength

“…3 Recently, Ti-based metallic glasses [4][5][6][7][8][9][10][11][12][13] and bimodal composites [14][15][16][17][18][19][20] have been developed with the aim to obtain high-strength Ti alloys. In the former case, they either contain the toxic constituent beryllium or have a low Ti concentration ͑ഛ50 at.…”

“…With respect to the yield strength, the UFG TiFe-Ta alloys exhibit 700-950 MPa higher yield strength than the Ti 60 Cu 14 Ni 22 Sn 4 Nb 10 alloy 14 and 200-1000 MPa higher yield strength than UFG Ti-Fe-based bimodal composites. [15][16][17][18] Altogether, the as-developed UFG Ti-Fe-Ta alloys exhibit not only a high fracture strength Ͼ2500 MPa but also a high yield strength Ͼ2000 MPa along with a plasticity of 5%-7.5%, which renders these alloys superior to high-strength Ti-based BMGs and bimodal composites. In addition, a low Ta concentration will not make these alloys expensive.…”

Deformation behavior of high strength metastable hypereutectic Ti–Fe–Co alloys

“…At the same time, new hypereutectic TieFe [11,12] and TieFeeCo [13,14] alloys obtained in the form of arc-melted ingots of about 20e40 mm diameter and 7e15 mm height, have shown high compressive strength (over 2 GPa) along with excellent ductility up to 7 and 16% for binary TieFe and ternary TieFeeCo alloys, respectively. The structure consists of a round-shaped primary dendritic cP2 intermetallic compound (IM) and a binary (cP2 IM þ cI2 b-Ti solid solution) eutectic [11e14].…”

Ultrafine Eutectic-Dendrite Composite Bulk Fe-B Alloy with Enhanced Ductility

“…In order to improve the room temperature ductility of ultrafine/nano-structured materials, the composite materials were designed by a dendrite phase rounding by an ultrafine/nano eutectic matrix in the past few years. [7][8][9][10][11][12][13][14] For example, Park et al 8) reported that the yield strength and plasticity of Fe 88 Nb 12 alloy were 1.4 GPa and 13.0%, respectively. Yield strength of 1.8 GPa and plasticity of 6.7% in the case of the Ti 65 Fe 35 was obtained by Louzguine et al 14) In summary, the structure of dendrite-ultrafine/nano composite can enhance the ductility of ultrafine/nano-structured materials.…”