Papers by Author: Kai Hui Zuo

Abstract: Alumina ceramics with inter-connected pores were fabricated by freeze casting method. The open porosity and fracture strength were controlled by the concentration of Al₂O₃ slurry and sintering temperature. Sintered at 1600°C, the open porosity and fracture strength of Al2O3 ceramics fabricated by the slurry with concentration of 70wt% are 46.4% and 23.8 MPa, respectively.

Abstract: (Al2O3+Ni) and (Al2O3+Ni)/Ni laminated materials were prepared by tape casting and hot pressing sintering. The mechanical properties of (Al2O3+20wt%Ni) laminated composites were higher than those of (Al2O3+50wt%Ni) composites and Al2O3 sample. The strengthening in the (Al2O3+Ni) composites mainly results from microstructure refinement of the alumina grain size, cracks bridging and crack deflection by the Ni particles. Results showed that the strength and fracture toughness of (Al2O3+Ni)/Ni laminated materials were higher than those of Al2O3/Ni laminated materials with the same layer numbers and thickness ratio. The good mechanical properties of (Al2O3+Ni) and (Al2O3+Ni)/Ni laminated materials result from the second phase of Ni particles in Al2O3 layers.