Microstructure and mechanical properties of Al2O3/Ni composites
Source abstract
Abstract
Abstract Ni-coated Al 2 O 3 powders were prepared by the heterogeneous precipitation method. After hot-pressing at 1300–1450 °C and 20 MPa, the density of homogeneous Al 2 O 3 /Ni composites ranges from ∼98% (NA4) to ∼94% (NA8.5) of the theoretical density. Examination by transmission electron microscope (TEM) and scanning electron microscopy (SEM) shows micrometer-size Ni grains to be located at the triple junctions, and with increasing Ni content, the fracture mode of Al 2 O 3 /Ni composites to change from intergranular mode to transgranular mode due to the thermal stresses. The strength and toughness of composites was much higher than that of the dense monolithic Al 2 O 3 . The strengthening and toughening mechanisms of the composites with respect to the microstructure are analyzed.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Advanced ceramic materials synthesis · Aluminum Alloys Composites Properties · Advanced materials and composites
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