摘要
The influence of oxygen（O） content on the microstructure and mechanical properties of cold rolled Ti-32.5 Nb-6.8 Zr-2.7 Sn-xO（TNZS-xO; x = 0,0.3.0.6; mass%） alloys after aging at temperature range from 350 to 600℃ for 24 h was investigated. Results showed that the cold rolled TNZS-xO alloys possess single βphase. During the aging process, O could not only effectively suppress the precipitation of ω phase but also retard the formation and decomposition of a phase. In addition, the corresponding temperatures of the maximal volume fraction of α phase precipitation and the（α＋β）/β transus temperatures of the TNZS-xO alloys were all increased with the increasing of O content. For mechanical properties, it was found that the strength and Young＇s modulus of the TNZS-xO alloys increased owing to the ω phase and/or a phase precipitation and decreased owing to the a phase decomposition. However, the elongation showed the opposite change tendency with the above mentioned strength. The mechanical properties of TNZS-xO alloys can be controlled over a wide range by subjecting to aging treatment and/or changing their 0 content. When aged at or below 450 ℃,the TNZS-xO alloys exhibit great potential to become a series of new candidates for biomedical applications since they possess high strength（870-1460 MPa）, low Young＇s modulus（45.1-75.6 GPa）, high strength-to-modulus ratio（0.018-0.02） and appropriate elongation（7.2%-14.9%）, which are superior to those of Ti-6 Al-4 V alloy and suitable for the use as bio-implant materials.
The influence of oxygen（O） content on the microstructure and mechanical properties of cold rolled Ti-32.5 Nb-6.8 Zr-2.7 Sn-xO（TNZS-xO; x = 0,0.3.0.6; mass%） alloys after aging at temperature range from 350 to 600℃ for 24 h was investigated. Results showed that the cold rolled TNZS-xO alloys possess single βphase. During the aging process, O could not only effectively suppress the precipitation of ω phase but also retard the formation and decomposition of a phase. In addition, the corresponding temperatures of the maximal volume fraction of α phase precipitation and the（α＋β）/β transus temperatures of the TNZS-xO alloys were all increased with the increasing of O content. For mechanical properties, it was found that the strength and Young＇s modulus of the TNZS-xO alloys increased owing to the ω phase and/or a phase precipitation and decreased owing to the a phase decomposition. However, the elongation showed the opposite change tendency with the above mentioned strength. The mechanical properties of TNZS-xO alloys can be controlled over a wide range by subjecting to aging treatment and/or changing their 0 content. When aged at or below 450 ℃,the TNZS-xO alloys exhibit great potential to become a series of new candidates for biomedical applications since they possess high strength（870-1460 MPa）, low Young＇s modulus（45.1-75.6 GPa）, high strength-to-modulus ratio（0.018-0.02） and appropriate elongation（7.2%-14.9%）, which are superior to those of Ti-6 Al-4 V alloy and suitable for the use as bio-implant materials.
基金
supported by the National Aerospace Science Foundation of China (Grant No. 20133069014)
the National Natural Science Foundation of China (Grant No. U1737103)
