Tensile behavior of tetragonal zirconia micro/nano-fibers and beams in situ tested by push-to-pull devices

The tensile mechanical behavior of tetragonal zirconia micro/nano-fibers and beams was studied with push-to-pull (PTP) devices equipped in an in situ nanoindenter. The small-volume ceramics generally experienced linear elastic deformation before fracture. Polycrystalline and oligocrystalline micro/nano-fibers exhibit a tensile strength of similar to 0.9-1.4 GPa, while single-crystal beams exhibit a much higher tensile strength (similar to 2.1-3.2 GPa). The tensile strength of the small-volume zirconia is found comparable to the corresponding compressive strength, which indicates the large discrepancy between the tensile and compressive strength observed in bulk zirconia becomes insignificant at micro/nano-scales. No martensitic transformation induced shape memory strain was detected in the zirconia fibers and beams. Further variation in dopant concentration and crystal orientation was explored for single-crystal beams and their significance in controlling the tensile strength was discussed. Our work offers a new insight into the mechanical behavior of tetragonal zirconia-based ceramics at small scales.

Automated summary

The tensile mechanical behavior of tetragonal zirconia micro/nano-fibers and beams was studied using an in situ nanoindenter. The study found that the tensile strength of small-volume zirconia is comparable to the compressive strength at micro/nano-scales, and no shape memory strain induced by martensitic transformation was detected.