ISSN:
1573-4803
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract Densification characteristics and fracture toughness of the alumina–mullite–zirconia (AMZ) composites fabricated by the colloidal mixing route were examined. The densification of boehmite–silica–zirconia precursor compacts was characterized by three distinct stages. Stage I was represented by a rapid shrinkage between 1100 and 1300°C and was caused by the viscous flow sintering of the SiO2 component. Stage II was characterized by a temporary cessation of the shrinkage caused by the mullitization. Stage III was represented by a restoration of the shrinkage for temperatures above 1450 °C. The α-Al2O3 seeding facilitated the formation of elongated grains in the AMZ composites, and these elongated grains correspond to α-Al2O3. The toughening caused by the microcrack nucleation was comparable to that by the t → m martensitic transformation and increased with increasing total content of zirconia.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1018590408443