Oscillatory pressure-assisted plastic joining of zirconia ceramics with excellent flexural strength

Here, an oscillatory pressure is applied for the plastic joining of zirconia ceramics. The shear strain of all joined sample is as high as 0.82. After plastic joining, no large pores are observed in the joint layer, and the joint samples remain dense. The grain size of all joined samples is nearly 50 % higher than that of the sample OS (joint free). The fracture mode of the sample changes from the intergranular fracture of the sample OS to the transgranular fracture of the joined samples. The maximum flexural strength of the joined sample is as high as 1552±225 MPa, which is 110 % higher than that of the parent material. Such an increase in flexural strength may be due to the removal of large pores under a high shear strain, grain boundary strengthening, and the introduction of high-density dislocations.