The microstructure in a small amount of Al2O3-doped Y2O3-stabilized tetragonal zirconia polycrystal (Y-TZP) sintered at 1100–1650 °C was examined to clarify the effect of Al3+ ions segregated at grain boundaries on cubic-formation and grain-growth processes. The sintering rate in Y-TZP was remarkably enhanced by Al2O3-doping. In addition, at temperatures >1500 °C, grain growth remarkably proceeded, and the fraction of the cubic phase increased in comparison with that of undoped Y-TZP. High-resolution electron microscopy and nanoprobe x-ray energy dispersive spectroscopy measurements revealed that no amorphous layer existed along the grain-boundary faces in Al2O3-doped Y-TZP and that Y3+ and Al3+ ions segregated at grain boundaries over widths of ∼10 and ∼6 nm, respectively. At 1100 °C, Al3+ ions started to segregate at grain boundaries, and the segregation peak of Al3+ ions increased as the sintering temperature increased. Cubic-formation and grain-growth behaviors in Al2O3-doped Y-TZP were reasonably interpreted by taking into account the effect of Al3+ ions segregating along grain boundaries.

The mechanical behavior of GaAsP alloy semiconductor was investigated by means of compressive deformation and compared with those of GaAs and GaP. The nature of collective motion of dislocations during deformation was determined by strain-rate cycling tests. The dynamic characteristics of dislocations in GaAsP were found to be similar to those in elemental and compound semiconductors such as Si, Ge, GaAs, and GaP. An alloy semiconductor has a component of the flow stress that is temperature-insensitive and is absent in compound semiconductors.