In situ scanning and transmission electron microscopy investigation on plastic deformation in a metastable β titanium alloy

Mechanism of {332}<113> Twinning Formation in Cold-Rolled Ti-Nb-Ta-Zr-O Alloy

“…Thus, the formation mechanism for the variants of {332}<113> twinning with low deformation energy corresponds to the shear-shuffle model and those with a high value correspond to the α"-assisted model. Among all the models of {332}<113> twinning formation, only Kawabata et al [12] and α"-assisted twinning models are adequately consistent with the results obtained in previous studies (such as Tane et al [4,44], Kawabata et al [12], Yao et al [13], Hanada et al [17], Talling et al [53], Morris Jr [57], and Takesue [58]) via the analysis of deformation energy based on the Hall-Petch-type relation. Moreover, Bishop et al [64] proposed that the sum of the absolute values of a physically possible set of shears producing a given strain is less than that of a set which is only geometrically possible, and the model of Kawabata et al [12] is well consistent with it.…”

“…The dominant deformation mechanism for β-type titanium (Ti) alloys corresponds to twinning and/or stress-induced martensitic transformation with decreasing levels of β phase stability [9]. Additionally, the common deformation twinning modes in β-type titanium alloys include {112}<111> and {332}<113> twins [10][11][12], and thus the predominant deformation mechanism corresponds to {332}<113> twinning formation only for β-type Ti alloys including Ti-Nb base [13] and Ti-Mo-based alloys at room temperature [14]. The {332}<113> twinning exhibits superior mechanical properties such as high elongation percentage (40% in Ti-Mo alloy) [14] and high strength(yield strength 750MPa roughly in Ti-Mo alloy) [15].…”

Grain Refinement of Ti-15Mo-3Al-2.7Nb-0.2Si Alloy with the Rotation of TiB Whiskers by Powder Metallurgy and Canned Hot Extrusion

“…Metastable β titanium alloys such as Ti-15Mo-3Al-2.7Nb-0.2Si are a promising candidate applied in aerospace and automotive industries, which have the advantages of high specific strength, excellent hot and cold workability, deep hardenability and oxidation resistance [1][2][3]. However, during hot working, metastable β titanium alloys coarsen rapidly at elevated temperatures, which could weaken their thermal stability and mechanical properties [4].…”

Microstructure and Mechanical Properties of Ti-35Nb-2Ta-3Zr Alloy by Laser Quenching

“…This work had triggered a research wave on the deformation mechanisms of β-titanium alloys and their influence on mechanical properties. Recently, a variety of deformation mechanisms in β titanium alloys have been found, including stress-induced phase transformations (β → α ′ , β → α ′′ or β → ω) (Ozan et al, 2017;Wang et al, 2017;Lai et al, 2018;Maghsoudlou et al, 2018;Yang et al, 2018;Gao et al, 2019), {332} twinning (Tobe et al, 2014;Lai et al, 2016Lai et al, , 2018Gao et al, 2019), {112} twinning (Yao et al, 2017;Gao et al, 2018), as well as dislocation slip (Lai et al, 2018;Gao et al, 2019). It was also revealed that the dislocation slip dominates the plastic deformation in the β-titanium alloys with higher stability, while reducing the stability of the β-titanium alloys activates other deformation mechanisms such as deformation twins and martensite transformation (Lai et al, 2016;Maghsoudlou et al, 2018).…”