Deformation-induced omega phase in modified Ti-29Nb-13Ta-4.6Zr alloy by Cr addition

作者：Li Qiang; Niinomi Mitsuo; Hieda Junko^*; Nakai Masaaki; Cho Ken

来源：Acta Biomaterialia, 2013, 9(8): 8027-8035.

DOI：10.1016/j.actbio.2013.04.032

• Biomaterial
• Titanium alloy
• Springback
• Deformation-induced
• Young's modulus

For spinal-fixation applications, implants should have a high Young's modulus to reduce springback during operations, though a low Young's modulus is required to prevent stress shielding for patients after surgeries. In the present study, Ti-29Nb-13Ta-4.6Zr alloy (TNTZ) with a low Young's modulus was modified by adding Cr to obtain a higher deformation-induced Young's modulus in order to satisfy these contradictory requirements. Two newly designed alloys, TNTZ-8Ti-2Cr and TNTZ-16Ti-4Cr, possess more stable beta phases than TNTZ. These alloys consist of single beta phases and exhibit relatively low Young's moduli of <65 GPa after solution treatment. However, after cold rolling, they exhibit higher Young's moduli owing to a deformation-induced omega-phase transformation. These modified TNTZ alloys show significantly less springback than the original TNTZ alloy based on tensile and bending loading-unloading tests. Thus, the Cr-added TNTZ alloys are beneficial for spinal-fixation applications.

• 出版日期2013-8