Fatigue crack propagation in short-fiber reinforced plastics
Journal Title: Frattura ed Integrità Strutturale - Year 2015, Vol 9, Issue 34
Abstract
The influence of fiber orientation on the crack propagation behavior was studied with single edgenotched specimens which were cut from an injection-molded plate of short-fiber reinforced plastics of polyphenylenesulphide (PPS) reinforced with 30wt% carbon fibers. Specimens were cut at five fiber angles relative to the molding direction, i.e. = 0° (MD), 22.5°, 45°, 67.5°, 90° (TD). Fracture mechanics parameters derived based on anisotropic elasticity were used as a crack driving force. Macroscopic crack propagation path was nearly perpendicular to the loading axis for the cases of MD and TD. For the other fiber angles, the crack path was inclined because the crack tended to propagate along inclined fibers. For mode I crack propagation in MD and TD, the resistance to crack propagation is improved by fiber reinforcement, when the rate is correlated to the range of stress intensity factor. The crack propagation rate, da/dN, was slowest for MD and fastest for TD. For each material, the crack propagation rate is higher for larger R ratio. The effect of R ratio on da/dN diminished in the relation between da/dN and the range of energy release rate, GI. Difference among MD, TD and matrix resin becomes small when da/dN correlated to a parameter corresponding the crack-tip radius, HGI, where H is compliance parameter. Fatigue cracks propagated under mixed loading of mode I and II for the fiber angles other than 0° and 90°. The data of the crack propagation rate correlated to the range of total energy release rate, Gtotal, lie between the relations obtained for MD and TD. All data of crack propagation tend to merge a single relation when the rate is correlated to the range of total energy release rate divided by Young’s modulus.
Authors and Affiliations
K. Tanaka, D. Yamada
Keywords
Related Articles
- EP ID EP106666
- DOI 10.3221/IGF-ESIS.34.33
- Views 84
- Downloads 0
Elastic wave propagation and stop-band generation in stronglydamaged solids
In this work, we study the propagation of elastic waves in elongated solids with an array of equallyspaceddeep transverse cracks, focusing in particular on the determination of stop-bands. We consider solidswith di...
A numerical study of two different specimen fixtures for the modified compact tension test – their influence on concrete fracture parameters
The modified compact tension test (MCT) may represent a new test configuration for the performance of static and other kinds of fatigue tests on concrete-like materials. Core drilling can be employed to obtai...
Esistenza del modo O in piastre tridimensionali con fori circolari ed ellittici soggette a modo II
Il problema di una piastra criccata tridimensionale soggetta a modo II è stato affrontato in letteratura dimostrando che l’effetto del coefficiente di Poisson provoca l’insorgere di una nuova singolarità accoppiata al ca...
Integrity and life estimation of turbine runner cover in a hydro power plant
This paper presents integrity and life estimation of turbine runner cover in a vertical pipe turbines, Kaplan 200 MW nominal output power, produced in Russia, and built in six hydro-generation units of hydroelect...
Analisi basata sugli sforzi locali della resistenza a fatica di giunzioni incollate di materiali compositi
Il lavoro prende spunto dai risultati di un’analisi sperimentale del comportamento a fatica di giunzioni incollate di materiali compositi laminati di elevato spessore formati da strati di unidirezionale e di tessuto di f...