放电等离子烧结温度对Ti-29Nb-13Ta-4.6Zr合金显微组织和力学性能的影响

Effect of Spark Plasma Sintering Temperatures on Microstructure and Mechanical Properties of Ti-29Nb-13Ta-4.6Zr Alloy

摘要:

利用放电等离子烧结技术（SPS）制备Ti-29Nb-13Ta-4.6Zr（TNTZ）合金，研究烧结温度对合金致密度、显微组织及力学性能的影响。结果表明：在950~1150 ℃烧结温度范围内合金具有较高的致密度和抗压强度，合金由β-Ti相与Ti-Nb-Ta-Zr固溶体形成的混合基体组织及少量未熔化的Nb、Ta、Zr金属颗粒组成。随着烧结温度的升高，合金致密度和抗压强度呈增大趋势，合金中混合基体组织尺寸越来越大且不断融合联结，难熔金属颗粒数量越来越少且尺寸越来越小。合金压缩弹性模量在58~60 GPa之间，说明具有良好的力学相容性，烧结温度变化对其影响较小。

Abstract:

Ti-29Nb-13Ta-4.6Zr alloys (wt%, TNTZ) were prepared by a spark plasma sintering (SPS) technique. The effects of the different sintering temperatures on the relative density, microstructure and mechanical properties of the alloys were investigated. In the sintering temperature range from 950 to 1150 oC, the alloys present a very high densification levels. All of the samples consist of β-Ti phase, Ti-Nb-Ta-Zr solid solution phase and some unmelted Nb, Ta, Zr metal particles. The alloys have a higher compressive strength, and they show a good room temperature compressive property. With the sintering temperatures increasing from 950 to 1150 oC, the relative density and the compressive strength of the alloys increase. The size of the matrix consisting of β-Ti phase and Ti-Nb-Ta-Zr solid solution phase increases and they bond further with each other. Furthermore, the size and the amount of the unmelted Nb, Ta, Zr metal particles decrease. The alloys exhibit low compressive elastic modulus in the range of 50~60 GPa, and it reveals the better mechanical compatibility.