Measurement of microscopic stress distribution of multilayered composite by X-ray stress analysis

In order to evaluate the effect of nano-sized dispersoid to microscopic stress distribution of multilayered composite, two kinds of multilayered composites, Al₂O₃/3 mol% Y₂O₃-stabilized ZrO₂ (3Y-TZP) and Al₂O₃/3Y-TZP(SiC), were fabricated. The latter composite contained nano-sized SiC dispersion within 3Y-TZP layers. The micro-residual stress measurement by X-ray diffraction (XRD) analysis for the monolithic 3Y-TZP and 3Y-TZP(SiC) nanocomposite layers within each composite revealed the existence of tensile and compressive stresses perpendicular and parallel directions to the layers, respectively. The tensile stress of approximately 200-300 MPa was observed to distribute across the zirconia layers in both composites. On the other hand, much higher compressive stress (i.e., 500-700 MPa) existed with a steep distribution across the layer especially for the monolithic Al₂O₃/3Y-TZP multilayered composite. However, both tensile and compressive stress distributions were found to be flattened when nano-sized SiC was incorporated into 3Y-TZP layer.