Compositionally graded composite of alumina-20% zirconia ( volume fraction ) was fabricated by using centrifugal casting incorporated with relatively thin slip. An EPMA analysis exhibited a nearly linear variation of the alumina/zirconia ratio along the centrifugal direction; zirconia tended to accumulate in the bottom section, while alumina in the .top section. Such a graded structure exhibited a considerably higher flexural strength when the alumina rich surface was subjected to a tensile stress than compositionally uniform composite of the same average composition. Fracture toughness measurement across the specimen thickness by indentation method revealed that the crack lengths along the vertical and horizontal directions were different. The anisotropy of the fracture toughness was accounted for by the variation of the residual stress across the specimen thickness.
参考文献
[1] | Chang J C;Velamakanni B V;Lange F F et al.Centrifugal consolidation of Al2O3 and Al2O3/ZrO2 composite slurries vs.interparticle potential[J].Journal of The American Chemical Society,1991,74:2201-2204. |
[2] | Biesheuvel P M;Verweij H .Calculation of the composition profile of a functionally graded materials produced by centrifugal casting[J].Journal of The American Chemical Society,2000,83:743-749. |
[3] | Li Xiao-dong .Fabrication of Nanocomposites in Alumina-Zirconia System by Using Centrifugal Slip Casting Method[D].Tottori University,Japan,2004. |
[4] | Xiaodong LI;Masaaki NAGASHIMA;Lei WANG .Consolidation Induced Microstructural Inhomogeneities in Al_2O_3-ZrO_2 Composites Prepared by Centrifugal Slip Casting[J].Journal of the Ceramic Society of Japan,2003(1300):890-896. |
[5] | Li X D;Wang L;Onda T et al.Fabrication of Al2O3-ZrO2 (3Y-TZP) composites with graded structure by centrifugal slip casting method[J].Materials Science Forum,2004,449-452:293-296. |
- 下载量()
- 访问量()
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%