Effect of Ti on the Structure and Mechanical Properties of Ti x Zr 2.5- x Ta Alloys.

To determine the effects of Ti and mixing entropy (Δ S mix ) on the structure and mechanical proper-ties of Zr-Ta alloys and then find a new potential energetic structural material with good me-chanical properties and more reactive elements, Ti x Zr 2.5- x Ta ( x = 0, 0.5, 1.0, 1.5, 2.0) alloys were investigated. The XRD experimental results showed that the phase transformation of Ti x Zr 2.5- x Ta nonequal-ratio ternary alloys depended not on the value of Δ S mix , but on the amount of Ti atoms. With the addition of Ti, the content of the HCP phase decreased gradually. SEM analyses revealed that dendrite morphology and component segregation increasingly developed and then weakened gradually. When x increases to 2.0, Ti x Zr 2.5- x Ta with the best mechanical properties can be ob-tained. The yield strength, compressive strength and fracture strain of Ti 2.0 Zr 0.5 Ta reached 883 MPa, 1568 MPa and 34.58%, respectively. The dependence of the phase transformation and me-chanical properties confirms that improving the properties of Zr-Ta alloys by doping Ti is feasible.