Multiscale damage analysis of the tension‐tension fatigue behavior of a low‐density sheet molding compound

Mohammadali Shirinbayan (1, 2)

1 LIFSE - Laboratoire d'Ingénierie des Fluides et des Systèmes Énergétiques
2 PIMM - Laboratoire Procédés et Ingénierie en Mécanique et Matériaux

This article presents the experimental findings of tension-tension stress-controlled fatigue tests performed on low-density sheet molding compound (LD-SMC). LD-SMC composite is a type of SMC including a polyester resin reinforced with chopped glass fibers bundles and hollow glass spheres. The coupled frequency-amplitude affects the nature of the overall fatigue response, which can be controlled by the damage mechanisms accumulation and/or by the self-heating. In fact, the self-heating produced a material softening and decreased the fatigue lifetime. For fatigue loading at 80 Hz, self-heating has been observed and yielded to a temperature rise to 65°C, which is more than a glass transition temperature of polyester. Thus, the polyester matrix is subjected to remarkable thermally activated modifications of its physical state. Multiscale damage analysis of the randomly-oriented sample in fatigue showed that the first observed damage phenomenon corresponds to the debonding of the hollow glass microspheres occurring in the fiber depleted zones.

Mots clés: composites; fibers; glass transition; SMC; thermosets

Domaines: Matériaux

Mohammadali Shirinbayan. Multiscale damage analysis of the tension‐tension fatigue behavior of a low‐density sheet molding compound. Journal of Applied Polymer Science, 2021, 138 (4), pp.1-12. ⟨10.1002/app.49721⟩. ⟨hal-03164584⟩