| Autor: |
Viorica E. Mindroiu, Mo Fung Cheung, Richard E. Robertson |
| Rok vydání: |
1985 |
| Předmět: |
|
| Zdroj: |
Composites Science and Technology. 22:197-207 |
| ISSN: |
0266-3538 |
| DOI: |
10.1016/0266-3538(85)90033-8 |
| Popis: |
The occurrence of fracture-energy-enhancing steps and welts on fracture surfaces of crosslinked matrix resins has been studied in an epoxy obtained from a trifunctional epoxy resin cured with an anhydride. It is suggested that the steps and welts arise from an underlying basic longitudinal texture, which was revealed by strongly tilting fracture specimens toward the collector in a scanning electron microscope. A model for the development of the basic longitudinal texture is proposed involving a meniscus instability of the propagating crack front, which gives rise to a series of fingers protruding into the bulk resin ahead of the nominal crack front. The periodicity of the basic longitudinal texture seen in the epoxy specimens studied was roughly 350 nm, which was independent of the epoxy resin: hardener ratio within at least 10% of stoichiometry. Because the periodicity of the basic longitudinal texture is roughly equal to the separation of the fracture surfaces immediately behind the crack, a considerable blunting of the crack by plastic deformation or yielding is suggested, a property that should depend on the matrix resin. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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