Tensile Property Evaluation of Additively Manufactured Ti–6Al–4V/Yttria-Stabilized Zirconia Composite Using Absolute Nonlinear Ultrasonic Technique

Directed energy deposition (DED), which is used to fabricate 3D metal components layer-by-layer, is a form of additive manufacturing. Yttria-stabilized zirconia (YSZ), which is a ceramic reinforcement material, enhances several mechanical properties in DED. However, the nondestructive evaluation of YSZ during DED has not been reported so far. This paper proposes a tensile property evaluation technique of Ti–6Al–4V (Ti64)/YSZ composites manufactured by DED using absolute nonlinear ultrasonics. This is unique in the following aspects: (1) a tensile property evaluation technique was developed for Ti64/YSZ composites; (2) absolute measurement of nonlinear elastic coefficient in Ti64/YSZ was achieved using ultrasound; (3) the technique shows potential for nondestructive online monitoring. First, the strengthening mechanisms of Ti64/YSZ in DED were analyzed using tensile testing and metallography. Then, the changes in tensile properties with variations in the YSZ conditions were nondestructively assessed using the developed technique. The evaluation results are consistent with the destructive tensile testing results. Furthermore, the evaluation performance was superior to the conventional nondestructive testing.