Threshold stress superplastic behavior and dislocation activity in a three-phase alumina–zirconia–mullite composite

Creep-related micromechanical behavior of zirconia-based ceramics investigated by nanoindentation

“…Moreover, the intragranular dislocation process does not readily occur because of the small grain size [4]. Therefore, grain boundary sliding accompanied by intergranular dislocation motion is the primary deformation mechanism [5]. However, the stress-directed diffusion creep process [3] is involved in grain growth, disappearance, and rearrangement [6].…”

“…However, the dislocation creep and slip creep play the major role under high stress level due to the high creep activation energy. The strain rate sensitivity at room temperature is significantly lower than that at high temperatures [3][4][5][6][7][8]. The atomic structure of ceramics is more complex than that of glass or crystals because of the existence of amorphous phases in the grain boundaries.…”

“…The time-dependent plastic deformation of materials, termed creep, is an important design criterion for high-temperature, high-stress, or long-term service conditions [3]. A great deal of research on the plastic behavior of zirconia ceramics at high temperature, especially for yttria-stabilized tetragonal zirconia, has been explored [3][4][5][6][7][8]. Grain boundary sliding has been consistently recognized as the primary deformation mechanism.…”

Superplasticity and superplastic-like flow in cubic zirconia with silica

“…5 for strain rates in the range of 10 -5 -10 -4 s -1 and this suggests that the occurrence of any sliding cannot be accommodated by slip within the adjacent grains. Although it is possible that stress concentrations may be generated by pile-ups of dislocations at the triple junctions [74], this is highly unlikely in the present material where there are rounded small grains of 8Y-CSZ and a malleable silica intergranular phase.…”

Reverse martensitic transformation in alumina–15vol% zirconia nanostructured powder synthesized by high energy ball milling

“…Partially stabilized zirconia (PSZ), i.e. solid solution (SS) of other oxides in zirconia has been observed as a promising material mainly due to their improved mechanical properties [5,6].…”