| Ceramics are materials that have good capability. They can bear high temperature, bear cauterization, resist oxidation, and has high strength and so on. But they have some deadly weakness, their toughness is so low and its brittleness is so great, what restrict it from been used broadly. Think about this, it is the continued emphases to research how to toughening the ceramics in the material domain. In past years, people want to find good way to toughening ceramics, now, there are two toughening mechanisms: one is to eliminate or reduce the crack bug in the ceramics and the second is to increase the toughness through appending some toughening sample, such as long fibre toughening, crystalloid toughening, changed substance toughening and so on. Of course these way have some effect, but their effect are limited, they can't resolve ceramics radical weakness. These years, people are inspired from some natural life that has especial configuration, such as conch, bamboo and so on. These life have high strength and good toughness. So, people begin to research laminated ceramics composites.Laminated ceramics composites have especial superposition configuration. It can design material in the macroscopical aspect besides chose different components. Now there some people begin groping research from the configuration design aspect. If we consider every layer as the configuration cell, there are two pivotal problems: (1) every cell's strength and toughening (2) how to chose a compatible interface. The laminated cell are high strength ceramics such as A1N, A^Os, TiB2 and so on. But interface are various, such as graphite, metal and so on. They can toughening the ceramics.In this experiment, we use the new technique of Spark Plasma Sintering System(SPS) to sinter laminated TiB2/BN ceramics. This technique is favorable to restrict the wafer growthing and get the ceramics that have symmetrical wafer. In the same time, we can control the sintering technic, retrench time, advise the efficiency of this equipment. This research shows that if we use technique of SPS, it will reduce sintering time and sintering temperature. It takes 10 minutes to finish one sintering. TiBi can be compact in 1600C and the relative consistency is 99%. The sintering temperature reduce 200C comparatively to the ordinary technic. The research also shows that ceramics of TiB2 sintered by SPS have better mechanicalcapability. Its strength increase from 520Mpa to 640Mpa, increase about 23%, comparatively to the ceramics sintered by Hot - Pressure.This experiment proves that if we use BN as the interface in TiB2, it can increase the toughness through some way of diffuse crack, deflex crack, passivate crack and so on. In the same time, it can keep the original strength. We have fabricated laminated TiB2/BN ceramics, T1B2 thickness is 300Mm, BN thickness is 40Mm. This sample's strength is 643Mpa(keep the original strength of TiB2 640Mpa), and toughness is 9.12Mpa.m1/2(about doubled the original toughness of TiB2 4.8 Mpa.m172).We studied the effect of the thickness of BN, we find that if the thickness is too great or too small, they all can't toughen the ceramics, the best thickness should be about 30 - 50Hm. And the same to the TiB2, its thickness should be about 150 - 300Mm. In addition, laminated ceramic mechanical capability is concerned to the proportion of the layer thickness. The better proportion is about 10. The toughening means of laminated TiB2/BN ceramics isn't the simple. It's the collective result of lots of means such as diffuse crack, deflex crack, passivate crack and so on. So laminated TiB2/BN ceramics can be designed from the macroscopical aspect, this way will be great available to our research.
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