J Mater Sci(2006)41:7425-7436 Fig. 7 Electron back-scatter diffraction(EBSD) pattern from the 12 grains(A-L) ndicated in Fig. 6 sample(20 vol% Al) before and after reaction bond- contrast to the above RBAO/TA laminates, the aTZ ng, confirming complete oxidation after the rBao layers are now in tension while the TA layers are in process. The final density of the RBAO/TA laminates compression, due to thermal expansion mismatch reached 97%TD. Figure 10b shows a typical optical between the adjacent layers. The residual stress micrograph of a sintered RBAO/TA laminate, in distribution is therefore expected to enhance crack which the thickness ratio of RBAO and TA layer is 3: 1 deflection at the interface between the zirconia and TA (alternating three stacks of gel-cast green RBAO tapes layers and one gel-cast green TA tape ). It has been found that Figure 1la shows an optical micrograph of a sin the resulting laminar interfaces are fairly straight in the tered ATZTA laminate, in which the thickness ratio laminate sample of ATZ and TA layer is 1: 1(alternating one gel-cast The second type of the texture-reinforced ceramic green ATZ tape and one gel-cast green TA tape). The laminate was developed from a fine-grain, texture-free, ATZ layer thickness has been found to be slightly ATZ matrix interleaved with highly TA interlayers In smaller than that of TA layer, which is due to larger 2 Springersample (20 vol% Al) before and after reaction bond￾ing, confirming complete oxidation after the RBAO process. The final density of the RBAO/TA laminates reached 97% TD. Figure 10b shows a typical optical micrograph of a sintered RBAO/TA laminate, in which the thickness ratio of RBAO and TA layer is 3:1 (alternating three stacks of gel-cast green RBAO tapes and one gel-cast green TA tape). It has been found that the resulting laminar interfaces are fairly straight in the laminate sample. The second type of the texture-reinforced ceramic laminate was developed from a fine-grain, texture-free, ATZ matrix interleaved with highly TA interlayers. In contrast to the above RBAO/TA laminates, the ATZ layers are now in tension while the TA layers are in compression, due to thermal expansion mismatch between the adjacent layers. The residual stress distribution is therefore expected to enhance crack deflection at the interface between the zirconia and TA layers. Figure 11a shows an optical micrograph of a sin￾tered ATZ/TA laminate, in which the thickness ratio of ATZ and TA layer is 1:1 (alternating one gel-cast green ATZ tape and one gel-cast green TA tape). The ATZ layer thickness has been found to be slightly smaller than that of TA layer, which is due to larger Fig. 7 Electron back-scatter diffraction (EBSD) patterns from the 12 grains (A–L) indicated in Fig. 6 7432 J Mater Sci (2006) 41:7425–7436 123