Low Young’s Modulus Ti–Nb–O with High Strength and Good Plasticity

Abstract

Oxygen was added to Ti38Nb (mass%) alloys to improve their mechanical properties. Ti38NbxO (x = 0.13, 0.24, 0.46, mass%) alloys were prepared by arc melting, and subsequently subjected to homogenization, hot rolling, and solution treatment. It was found that adding oxygen suppresses the martensite transformation and exhibits strong solution strengthening effect. Single ¢ phase is obtained in Ti38Nb0.24O, whereas Ti38Nb0.13O is composed of both ¡AA and ¢ phases. Both alloys exhibit double yielding phenomena during tension, indicating a stress-induced martensitic transformation. Ti38Nb0.46O exhibits a non-linear deformation, a low Young's modulus of 62 GPa, high tensile strength up to 780 MPa, and elongation around 23%, which are promising characteristics for biomedical applications.

Manipulating the ordered oxygen complexes to achieve high strength and ductility in medium-entropy alloys

“…1a ). The loss of ductility might originate from suppression of the martensite phase transformation or/and twin formation, as reported previously in some dual-phase titanium alloys 9 , 18 , 19 .

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“…5a ), i.e., in the alloys with a low amount of Nb, oxygen addition suppresses twinning and the martensite phase transformation (Fig. 5b ), leading to the significant loss of ductility 9 , 18 , 19 . The addition of excess oxygen results in the grain boundary segregation (Fig.…”

Effect of Thermo-mechanical Treatment on Microstructure and Mechanical Properties of Two-phase TiNbO Alloy

“…The addition of O to β Ti alloys has been found to some special effects. Oxygen, which is regarded as an interstitial element, has a significant solid solution strengthening effect and keeps its Young's modulus relatively low [9][10][11]. It was reported by Kim [12] that the fracture stress of solution treated specimen increased with increasing oxygen content.…”

Estudo dos efeitos da adição de oxigênio na estabilidade microestrutural e nas propriedades mecânicas de ligas do sistema Ti-Nb

“…No entanto, é provável que o oxigênio tenha tido alguma influência nas suas respectivas frações volumétricas. O oxigênio é conhecido por suprimir a fase α", diminuindo a temperatura inicial de formação da martensita (Ms) (LI et al, 2018a). Ou seja, embora ele seja um elemento α estabilizador, ele tende a favorecer a retenção da fase β em detrimento da fase α" durante um resfriamento brusco, levando, portanto, a uma fração mais alta de β na liga.…”

“…Isto pode explicar a ausência do pico nos resultados das ligas com 15% de Nb. BÖNISCH et al, 2015;LI et al, 2018b;OZAKI et al, 2004;ZHANG et al, 2020). As ligas com 15% de Nb exibiram os menores módulos de elasticidade, em torno de 59 GPa, o que está próximo a 65 GPa relatado por Aleixo et al (2008).…”