Multiaxial deformation and strain-induced crystallization around a fatigue crack in natural rubber
Language
en
Article de revue
This item was published in
Engineering Fracture Mechanics. 2014, vol. 123, p. 59-69
Elsevier
English Abstract
The study of fatigue crack propagation in elastomers is an essential prerequisite to improve the service life of tire products. Natural rubber is a key compound in tires, because of its unique mechanical properties and ...Read more >
The study of fatigue crack propagation in elastomers is an essential prerequisite to improve the service life of tire products. Natural rubber is a key compound in tires, because of its unique mechanical properties and more particularly its remarkable resistance to fatigue crack growth as compared to synthetic rubbers. To explain this resistance, the literature often mentions the phenomenon of strain-induced crystallization which takes place at fati- gue crack tips in natural rubber and then reinforces it. In the present study, an original experimental set-up that couples synchrotron radiation with a homemade mechanical fati- gue machine is developed to investigate both strain-induced crystallization and deforma- tion multiaxiality around fatigue cracks in natural rubber. During uninterrupted fatigue tests, recording of wide-angle X-ray diffraction patterns is performed in the crack tip region providing the two-dimensional spatial distribution of both crystallinity and principal strain directions. In particular, the influence of loading conditions on the size of the crystallized zone is investigated and related to fatigue crack growth rates. Finally, measurements of deformation multiaxiality, i.e. principal strain directions and change in thickness, obtained by this method are successfully compared with digital image correlation results.Read less <
English Keywords
Digital image correlation
Synchrotron radiation
Natural rubber
Strain-induced crystallization
Fatigue crack
Origin
Hal imported