The characteristics of fatigue crack initiation in Ti-5AI-4Sn-2Zr1Mo-O.7Nd-O.25Si alloy wereStudied. Two modes Of fatigue crack initiation were found. The Nd-rich phase particles displaybetter resistance to fatigue cr...The characteristics of fatigue crack initiation in Ti-5AI-4Sn-2Zr1Mo-O.7Nd-O.25Si alloy wereStudied. Two modes Of fatigue crack initiation were found. The Nd-rich phase particles displaybetter resistance to fatigue crack initiation than the matrix at lower stress.展开更多
A novel method has been developed to rapidly deposit bone-like apatite with the assistance of ultraviolet （UV） light irradiation on the nanostructured titania in the simulated body fluid （SBF）. The process has thr...A novel method has been developed to rapidly deposit bone-like apatite with the assistance of ultraviolet （UV） light irradiation on the nanostructured titania in the simulated body fluid （SBF）. The process has three main steps： Ti-24Nb-4Zr-7.9Sn alloy was heated at 650℃ for 3 h, UV-light illumination in air for 4 h and soaking in the SBF for 3 d. A titania coating consisted of main rutile formed on the thermal oxidized Ti-24Nb-4Zr- 7.9Sn alloy. The UV not only converted the futile surface from hydrophilic to hydrophobic but also stimulated high surface activity. After 4 h UV illumination, the contents of Ti3＋ and hydroxyl groups on the oxidized sample were increased, while that of lattice O decreased. After 3 d of soaking in the SBF, a compact and uniform layer of carbonated hydroxyapatite （CHA） particles was formed on the UV-illuminated rutile surface whereas there was a few of HA to be viewed on the surface of as-oxidized Ti-24Nb-4Zr-7.9Sn alloy. Our study demonstrates a simple, fast and cost-effective technique for growing bone-like apatite on titanium alloys.展开更多
Ti-32.5 Nb-6.8 Zr-2.7 Sn（TNZS,wt%） alloy was produced by using vacuum arc melting method,followed by solution treatment and cold rolling with the area reductions of 50% and 90%.The effects of cold rolling on the mic...Ti-32.5 Nb-6.8 Zr-2.7 Sn（TNZS,wt%） alloy was produced by using vacuum arc melting method,followed by solution treatment and cold rolling with the area reductions of 50% and 90%.The effects of cold rolling on the microstructure,texture evolution and mechanical properties of the experimental alloy were investigated by optical microscopy,X-ray diffraction,transmission electron microscopy and universal material testing machine.The results showed that the grains of the alloy were elongated along rolling direction and stress-induced α＇＇ martensite was not detected in the deformed samples.The plastic deformation mechanisms of the alloy were related to {112} 111 type deformation twinning and dislocation slipping.Meanwhile,the transition from γ-fiber texture to α-fiber texture took place during cold rolling and a dominant {001} 110α-fiber texture was obtained after 90% cold deformation.With the increase of cold deformation degree,the strength increased owing to the increase of microstrain,dislocation density and grain refinement,and the elastic modulus decreased owing to the increase of dislocation density as well as an enhanced intensity of {001} 110α-fiber texture and a weakened intensity of {111} 112γ-fiber texture.The 90% cold rolled alloy exhibited a great potential to become a new candidate for biomedical applications,since it possesses low elastic modulus（47.1 GPa）,moderate strength（883 MPa） and high elastic admissible strain（1.87%）,which are superior than those of Ti-6 Al-4 V alloy.展开更多
文摘The characteristics of fatigue crack initiation in Ti-5AI-4Sn-2Zr1Mo-O.7Nd-O.25Si alloy wereStudied. Two modes Of fatigue crack initiation were found. The Nd-rich phase particles displaybetter resistance to fatigue crack initiation than the matrix at lower stress.
基金The authors acknowledge the financial support for this work from the National Natural Science Foundation of China （Grant No. 51371126） and the Science and Technology Plan Project of Binhai new area of Tianjin （2012-BK120024）.
文摘A novel method has been developed to rapidly deposit bone-like apatite with the assistance of ultraviolet （UV） light irradiation on the nanostructured titania in the simulated body fluid （SBF）. The process has three main steps： Ti-24Nb-4Zr-7.9Sn alloy was heated at 650℃ for 3 h, UV-light illumination in air for 4 h and soaking in the SBF for 3 d. A titania coating consisted of main rutile formed on the thermal oxidized Ti-24Nb-4Zr- 7.9Sn alloy. The UV not only converted the futile surface from hydrophilic to hydrophobic but also stimulated high surface activity. After 4 h UV illumination, the contents of Ti3＋ and hydroxyl groups on the oxidized sample were increased, while that of lattice O decreased. After 3 d of soaking in the SBF, a compact and uniform layer of carbonated hydroxyapatite （CHA） particles was formed on the UV-illuminated rutile surface whereas there was a few of HA to be viewed on the surface of as-oxidized Ti-24Nb-4Zr-7.9Sn alloy. Our study demonstrates a simple, fast and cost-effective technique for growing bone-like apatite on titanium alloys.
基金financially supported by the National Aerospace Science Foundation of China (Grant No.20133069014)
文摘Ti-32.5 Nb-6.8 Zr-2.7 Sn（TNZS,wt%） alloy was produced by using vacuum arc melting method,followed by solution treatment and cold rolling with the area reductions of 50% and 90%.The effects of cold rolling on the microstructure,texture evolution and mechanical properties of the experimental alloy were investigated by optical microscopy,X-ray diffraction,transmission electron microscopy and universal material testing machine.The results showed that the grains of the alloy were elongated along rolling direction and stress-induced α＇＇ martensite was not detected in the deformed samples.The plastic deformation mechanisms of the alloy were related to {112} 111 type deformation twinning and dislocation slipping.Meanwhile,the transition from γ-fiber texture to α-fiber texture took place during cold rolling and a dominant {001} 110α-fiber texture was obtained after 90% cold deformation.With the increase of cold deformation degree,the strength increased owing to the increase of microstrain,dislocation density and grain refinement,and the elastic modulus decreased owing to the increase of dislocation density as well as an enhanced intensity of {001} 110α-fiber texture and a weakened intensity of {111} 112γ-fiber texture.The 90% cold rolled alloy exhibited a great potential to become a new candidate for biomedical applications,since it possesses low elastic modulus（47.1 GPa）,moderate strength（883 MPa） and high elastic admissible strain（1.87%）,which are superior than those of Ti-6 Al-4 V alloy.
