A STRONG AND DAMAGE-TOLERANT OXIDE LAMINATE

A novel laminar oxide composite was developed, This oxide laminate, wh ich was fabricated by hot pressing, consisted of three types of layers , which were stacked in a repeating sequence of YPO4, yttria-stabilize d ZrO2, 30 vol% yttria-stabilized ZrO2-70 vol% Al2O3, and yttria-stabi lized ZrO2, The behavior of the oxide laminate was evaluated by four-p oint flexural testing and the indentation technique, The flexural stre ngth from one test was 358 MPa, and the load-displacement curve of thi s test displayed a graceful failure, Pronounced interfacial delaminati on contributed to a high work of fracture and damage tolerance. These properties have rarely been observed in oxide composites and are compa rable to those of non-oxide composites, such as SIC/graphite, SIC/BN, and Si3N4/BN laminates.