Al2O3/TiC/(MoSi2+Mo2B5) multilayer composites prepared by tape casting

A new multilayer composite (MLC) with a super-plastic layer, a hard layer a nd a weak interface was proposed in this paper. The hard layer can provide the MLC high temperature strength, the super-plastic layer can deform plast ically at high temperatures and disperse the applied stress and stop the ad vance of the crack, and the weak interface can deflect the propagating crac k at room temperature. Such MLC was prepared by tape casting in the Al2O3/T iC/MoSi2 + Mo2B5 system in the present work. In this system Al2O3 was as th e hard layer, MoSi2 + Mo2B5 was as the super-plastic layer and TiC was as t he weak interface. The microstructures and the stress-displacement behavior s of the MLCs were investigated. If was found that such design is effective on the increase of fracture energy both at room temperature and at high te mperatures, and the strength at high temperatures could be remained in a re latively high level. (C) 1999 Elsevier Science Limited. All rights reserved .