화학공학소재연구정보센터
Journal of the American Ceramic Society, Vol.85, No.7, 1763-1769, 2002
Creep of duplex alumina-titanium nitride polycrystalline microstructures
Compression creep results in an inert atmosphere are presented for fine-grained Al2O3-TiN composites deformed under a stress range of 10-50 MPa stress and a temperature range of 1250degrees-1400degreesC. The effects of TiN content (10-70 vol%) and the preparation route (i.e., reactive versus nonreactive hot pressing) are considered. Al2O3 and TiN both are efficient grain-growth inhibitors, relative to each other; thus, deformation develops in stable equiaxed microstructures. Except for low TiN contents (10 and 20 vol%), the processing route does not markedly influence the observed strain rates, at least up to a strain of -0.16. In all cases, deformation occurs mainly via interfacial/grain-boundary sliding, and its rate is enhanced in approximate proportion to the amount of Al2O3/TiN interfacial area. The deformation rate seems to be limited by, either some interface reaction or a complex boundary diffusional mechanism that occurs at the Al2O3 grain boundaries.