Effect of Thermo-Mechanical Treatments on the Microstructure and Mechanical Properties of the Metastable beta-type Ti-35Nb-7Zr-5Ta Alloy

Autor(es)

Plaine, Athos Henrique ^[1] ; da Silva, Murillo Romero ^[1] ; Bolfarini, Claudemiro ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos, Dept Engn Mat, Rod Washington Luis Km 235, BR-13565905 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: MATERIALS RESEARCH-IBERO-AMERICAN JOURNAL OF MATERIALS; v. 22, n. 1 2019.
• Citações Web of Science: 0

Resumo

In this work, theoretical composition design and thermo-mechanical treatments were combined in order to improve the mechanical compatibility of a biomedical beta-type titanium alloy. By applying a composition design theory, cold rolling and low temperature aging, a metastable beta-type Ti-35Nb-7Zr-5Ta (wt%) alloy with an elastic modulus of 47 GPa and a yield strength of 730 MPa was successfully fabricated. This combination of high yield strength and low elastic modulus resulted in enhanced elastic recoverable strain of 1.7%, which is much higher than that of the conventional metallic biomaterials. The microstructure responsible for the much sought-after mechanical properties was observed to be mainly consisted of a homogeneous distribution of nanometer-sized omega- and alpha-precipitates in a beta-phase matrix obtained via cold rolling plus short-time aging at low temperature, i.e. aging at 673 K for 20 min. These precipitates increase the strength of the material by hindering the motion of dislocations while the beta-matrix with relatively low content of beta-stabilizers gives rise to the observed low elastic modulus. By extending aging time, a higher strength is reached at the expense of an undesirable increasing in elastic modulus. (AU)

• Processo FAPESP: 16/17502-7 - Desenvolvimento e caracterização de novas ligas de titânio para aplicação em endopróteses vasculares (stents)
• Beneficiário: Athos Henrique Plaine
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado