Fatigue behavior of additively manufactured Ti3Al2V alloy

In this study, we measured the tensile, compression, and fatigue behavior of additively manufactured Ti3Al2V as a function of build orientation. Ti3Al2V alloy was prepared by mixing commercially pure titanium and Ti6Al4V in 1:1 wt. ratio. Laser powder bed fusion-based additive manufacturing technique was used to fabricate the samples. Tensile tests resulted in an ultimate strength of 989 +/- 8 MPa forTi3Al2V. Ti6Al4V 90 degrees orientation samples showed a compressive yield strength of 1178 +/- 33 MPa and that for Ti3Al2V 90 degrees orientation samples were 968 +/- 24 MPa. By varying the build orientation to account for anisotropy, Ti32 45 degrees and Ti32 0 degrees samples displayed almost similar compressive yield strength values of 1071 +/- 16 and 1051 +/- 18 MPa, respectively, which were higher than that of Ti32 90 degrees sample. Fatigue loading revealed an endurance limit (10 million cycles) of 250 MPa forTi6Al4V and of 219 MPa for Ti3Al2V built at 90 degrees orientation. The effect of the build orientation was significant under fatigue loading; Ti3Al2V built at 45 degrees and 0 degrees orientations displayed endurance limits of 387.5 MPa and 512 MPa, respectively; more than two-fold increment in endurance limit was observed. In conclusion, the superior attributes of Ti3Al2V alloy over Ti6Al4V alloy, as demonstrated in this study, justify its potential in load-bearing applications, particularly for use in orthopedic devices.