| 1. |
- Nilsson, M., et al.
(författare)
-
A Critical Appraisal of the Interfacial Toughness of Ceramic Matrix Composites Using Indentation Techniques
- 1999
-
Ingår i: Key Engineering Materials. - 1013-9826 .- 1662-9795. ; 161-163:675-680, s. 675-680
-
Tidskriftsartikel (refereegranskat)abstract
- Advanced ceramic matrix composites provide a challenge for both manufacturer and user necessitating better techniques to critically appraise their properties. Interfacial toughness and the change of this property with application time at elevated temperature in hostile environments is of paramount importance for structural integrity/reliability of these materials. The present study investigates two such composite systems; a mullite matrix reinforced with silicon carbide fibres, and a novel oxide composite using sapphire fibres within an alumina-zirconia matrix. The interfacial toughness between the fibres and matrix was evaluated using nano- and micro-indentation fracture toughness methodologies. The results are interpreted in terms of recent theoretical interfacial fracture mechanics analysis by Hutchinson and Suo[1] for cracks approaching and extending along an interface. Nano-indentation has also been used to evaluate the intrinsic elastic/plastic properties of the CMC materials
|
|
| 2. |
|
|
| 3. |
- Antti, Marta-Lena, et al.
(författare)
-
Thermal expansion behaviour of high melting point oxides
- 1999
-
Ingår i: Key Engineering Materials. - 1013-9826 .- 1662-9795. ; 164-165, s. 279-282
-
Tidskriftsartikel (refereegranskat)abstract
- The thermal expansion characteristics of the reinforcement and matrix constituents in ceramic composites have a strong influence on a number of aspects of the composite performance. Thus the toughness and strength of the composite can be influenced by local residual stresses due to the thermal expansion mismatch of different phases. Moreover, in individual polycrystalline phases, local stress variations from grain to grain, generated as a result of anisotropy of thermal expansion in combination with anisotropy of elasticity can influence strength and toughness in similar ways. In the present study, reported data on the thermal expansion coefficients of oxides having potential as constituents in high temperature composites are reviewed and complemented with additional measurements made using high temperature X-ray diffraction
|
|
| 4. |
- Babushkin, O., et al.
(författare)
-
Diffusionless phase transition in the ZrO2-TiO2 system
- 1994
-
Ingår i: Solid-solid phase transformations. - Warrendale, Pa. : Minerals, Metals & Materials Society. - 0873392787 ; , s. 743-748
-
Konferensbidrag (refereegranskat)abstract
- Stable and metastable phase relationships in the ZrO2-TiO2 system were investigated using homogeneous samples with ZrO2 particles of different surface area. Phase analysis associated with the diffusionless and reversible monoclinic-tetragonal transition has been performed with high temperature X-ray diffractometry. The rate of the phase transition, depending on powder morphology, is presented. The character of the hysteresis loop associated with the martensitic phase change for pure ZrO2 and for the ZrO2-TiO2 system is discussed
|
|
| 5. |
- Greaves, C., et al.
(författare)
-
Enhancing speech intelligibility using visual images
- 1993
-
Ingår i: Human-computer interaction : proceedings of the Fifth International Conference on Human-Computer Interaction, (HCI International '93), Orlando, Florida, August 8 - 13, 1993. - Amsterdam : Elsevier. - 044489540X ; , s. 1097-1102
-
Konferensbidrag (refereegranskat)
|
|
| 6. |
|
|
