Favorable microstructural modulation and enhancement of mechanical properties of Ti–Fe–Nb ultrafine composites

Abstract

Microstructure evolution and its influence on the mechanical properties of (Ti 65.5 Fe 34.5 ) 100Àx Nb x (x ¼ 0, 3, 5 and 7) ultrafine composites has been investigated. The Nb-containing alloys exhibit simultaneously improved compressive mechanical properties, i.e. high yield (1.9-2.2 GPa) and fracture (2.2-2.6 GPa) strength together with large plasticity (6-13%), due to a favorable modulation of their ultrafine eutectic microstructure. The enhanced mechanical properties are strongly related to the lengthscale, volume fraction and distribution of proeutectic phase as well as to the refinement and interphase coherency of the alternating ultrafine eutectic layers.

High‐strength bimodal ultrafine Ti‐based alloys with enhanced ductility

“…The (Ti 65 Fe 35 ) 89.15 Sn 3.85 Nb 7 alloy exhibits a significantly decreased strength as shown in figure . The (Ti 65 Fe 35 ) 93.15 Sn 3.85 Nb 3 alloy reveals a similar plastic strain and a higher compressive strength in comparison with the (Ti 65 Fe 35 ) 93 Nb 7 (2.57 GPa) and alloy . Figure displays SEM secondary electron (SE) images of the fracture surfaces of the specimens after compression at ambient temperature.…”

“… reported that eutectic and hypereutectic Ti‐Fe alloys consisting of A2 β‐Ti and B2 TiFe phases show a strength of ∼2 GPa and reasonable ductility of 4–7% in compression. The improved mechanical properties of eutectic and hypereutectic Ti‐Fe alloys have been reported by the additions of third elements such as Sn, Ga, Co, Ta, and Nb . The addition of 3.85 at.% Sn to eutectic Ti‐Fe alloys results in the increased strength and ductility .…”

Transmission electron microscopy study of the microstructure of a Ti–Fe–Zr alloy

“…Recently, less-costly, lower-density binary Ti-Fe alloys with ultrafine β-Ti plus TiFe microstructures were observed to exhibit a strength of 2000 MPa and 4-7% ductility [5,6]. Additions of Sn, Ta, Co, and Nb can further increase the strength and ductility of eutectic and hypereutectic Ti-Fe alloys [5][6][7][8][9][10][11]. Zirconium and titanium are congener transition metal elements in Group IV of the periodic table.…”

Microstructure and mechanical properties of Fe–Si–Ti–(Cu, Al) heterostructured ultrafine composites

“…Recently, ductile bimodal ultrafine eutectic composites without additional micrometer-size toughening phase have been developed [12][13][14][15]. In this case, the length scale heterogeneity of the eutectic phase contributes to the plasticity enhancement in such high strength nano-/ultrafine eutectic composites [16][17][18][19].…”