Yttria-stabilized zirconia-aluminum matrix composites via ultrasonic additive manufacturing

High-integrity ceramic-metal composites combine electrical, thermal, and corrosion resistance with excellent mechanical robustness. Ultrasonic additive manufacturing (UAM) is a low temperature process that enables dissimilar material welds without inducing brittle phases. In this study, multiple layers of Yttria-stabilized zirconia (YSZ) films are jointed between layers of Al 6061-H18 matrix using a 9 kW UAM system. UAM is advantageous over existing metal-ceramic composite fabrication techniques by continuously joining ceramics to metals at a speed of 2 m/min while requiring a moderate temperature that is 55% of the melting point of aluminum. The welding interface, which is found to include a 10 nm thick diffusion zone, is investigated using optical microscopy and energy-dispersive X-ray (EDX) spectroscopy. The shear strengths of the as-welded and heat-treated composites are 72 MPa and 103 MPa, respectively. The shear deformation and failure mechanism of the YSZ-Al composites are investigated via finite element modeling.