The atomic size of tantalum and tungsten is close to the lattice type, and they have a large solid solubility in Ta, which is an ideal solid solution strengthening element for Ta alloy. The solid solution element W can improve the high temperature strength and thermal stability of Ta base alloy, and can effectively expand the application field of Ta alloy. The results show that the addition of W can enhance the flow stress of the alloy at high temperature and reduce the sensitivity to temperature and strain rate. The mechanical properties of Ta-2.5W, Ta-5W and Ta-7.5W alloys at room temperature are studied. It is pointed out that when the content of W is less than 5%, Ta-W alloys can achieve complete solution and form Ta-W solid solution alloys. When the content of W is greater than 5%, W cannot be solidly dissolved into Ta matrix. However, with the increase of W content, the precipitates can nail the grain boundary, inhibit the grain boundary movement in the alloy structure, refine the grain, enhance the strength of the alloy, but reduce the plastic deformation ability of the alloy. The high temperature tensile test of Ta-W alloy under different processing conditions was carried out in vacuum environment. The results show that the Ta-W alloy with high W content has better mechanical properties at high temperature under the same process conditions.
Tantalum-niobium (Ta-Nb) alloy system, due to Ta, Nb elements have good biocompatibility and non-toxic characteristics of human body, is gradually becoming the next generation of biomedical metal materials. As a substitute for V, Co, Al and Ni, Ta and Nb elements have complete corrosion resistance and excellent biocompatibility to the human environment. The low modulus of this kind of alloy ensures that the alloy material has a good bonding ability with bone and other tissues, and it is a new biological material that has attracted much attention in recent years.
Ta-10Nb porous alloy for clinical use was successfully prepared by sponge impregnation and sintering technology. It is pointed out that the elastic modulus and comprehensive strength of porous Ta-10Nb alloy are 2.54GPa and 83.43MPa, respectively, and the mechanical properties of porous Ta-10Nb alloy are similar to that of cancelous bone. Moreover, the pore morphology of porous Ta-Nb alloy shows a good three-dimensional interconnecting network opening structure, which has a broad application prospect in the field of biomedical engineering.
