New Low Modulus Titanium Alloy Material For Biology Engineer

Researches on the titanium alloy biomaterials develop with the need of human to the health and good living condition. Titanium alloy biomaterials have experienced several periods : commercial titanium, traditional TC4(Ti6A14V) alloy, titanium alloys with no aluminum element, titanium alloys with no aluminum and no vanadium element, and low modulus titanium alloys. In the article, to get low modulus titanium alloy biomaterials, Ti-Nb alloys and Ti-Nb-Ta-Zr alloys have been studied.The influence of Nb element to the moduli of Ti-Nb binary alloys has been analyzed at first. By applying orthogonal design method and d-electron theory, the composition of Ti-Nb-Ta-Zr alloys have been designed and analyzed. Studies on the microstructures, mechanical properties, and moduli of alloys under different thermal treatment conditions have been completed by mechanical test, optical microscope, scanning electron microscope (SEM), X-ray diffraction (XRD). According the results of XRD. the lattice constant of different phase in the alloys have been calculated and analyzed. And the expansion test and differential thermal analysis have been done to the alloy Ti20Nbl3Tal3Zr which has good composite properties. At last, the study on the corrosion resistance has been done by cooperating with Medical University of China.TheTi-Nb series binary alloys have low moduli under solution, which are the 50~70 percent of the modulus of TC4 alloy (about 11 OGPa). The Ti-20Nb alloy has the lowest modulus, about 58GPa. the Ti-Nb alloys have lower tensile strength under room temperature. The Rm is 635±30MPa, and Rp0.2 is 330~370MPa. But the δ and (?) are high, which are 19-32 percent and 31-69 percent. The plasticity of them are good.Ti20Nbl3Tal3Zr alloy has the best composite properties in the Ti-Nb-Ta-Zr alloys that have been studied. Under solution, its modulus can reach 62GPa; the Rm and Rp0.2 can reach 650MPa and 480MPa. Under solution and aging, the modulus can reach 68GPa, the room temperature mechanical properties are as follows: Rm≥720MPa, Rp0.2≥620 MPa, A...