The Investigation On Mechanical Properties Of Zirconium Alloys In Biomedical Research And The Nuclear Energy Applications

In the field of biomedical zirconium alloys, according to the different requirements of the mechanical properties, the Zr-Mo, Zr-Nb and Zr-Cu alloys are designed and preparation:(1) A ?-type Zr-Mo-Ti alloys for biological hard tissue replacements, which have only one phase (?-Zr) at room temperature. These ?-type Zr-Mo-Ti alloys exhibit high compressive strength (1469-1584 MPa), high yield strength (1175-1375 MPa), high elastic energy (21-28 MJ/m3) and low Young's modulus (32-35 GPa), together with plastic strain (11-25%); (2) A new ?-type Zr-Nb-Ti alloys for biological hard tissue replacements, which have only one phase (?-Zr) at room temperature. These single ?-Zr alloys can effectively decrease the elastic modulus (28-31 GPa) and keep excellent plasticity for zirconium alloy. The plastic strain of all Zr-Nb-Ti alloys is more than 40%. These P-type Zr-Nb-Ti alloys moderate compressive strength (1044-1325 MPa) and yield stress (854-1080 MPa) and high elastic energy (12-20 MJ/m3); (3) In situ synthesized low modulus biomedical Zr-Cu-Nb alloys, the Zr3Cu particles is obtained in as-cast samples and zirconium alloy can produce a second phase strengthening by the second phase Zr3Cu. At the same time, the alloy element Nb is added in Zr-matrix to adjust the shape of Zr3Cu, so that the different mechanical properties zirconium alloys can be obtained. These alloys exhibited moderate compressive strength (1150-1300 MPa), yield stress (750-1000 MPa), favorable plastic strain (19%-27%), high elastic energy (11 MJ/m3-16 MJ/m3) and low Young's modulus (25 GPa-31 GPa).In the field of nuclear energy applications, a novel high-strength ternary Zr-Al-Sn alloys with martensite structure is prepared. All samples have only one phase:a-Zr. According to the microstructure analysis, confirmed that the microstructure of all samples is lath martensite. Mechanical tests show that these Zr-5Al-xSn alloys exhibit high compressive strength (1250-1450 MPa), high yield stress (800-1000 MPa), and favorable plastic strain (18-23%). In addition, zirconium alloys by heat treatment, it is found that the yield stress is increased with heat treatment, but compressive strength and plastic strain is decreased.